Energy delivery systems and uses thereof

ABSTRACT

The present invention relates to comprehensive systems, devices and methods for delivering energy to tissue for a wide variety of applications, including medical procedures (e.g., tissue ablation, resection, cautery, vascular thrombosis, treatment of cardiac arrhythmias and dysrhythmias, electrosurgery, tissue harvest, etc.). In certain embodiments, systems, devices, and methods are provided for treating a tissue region (e.g., a tumor) through application of energy.

The present application claims priority to U.S. Provisional ApplicationSer. No. 60/831,056, filed Jul. 14, 2006, and 60/853,911, filed Oct. 24,2006, each herein incorporated by reference in their entireties.

FIELD OF THE INVENTION

The present invention relates to comprehensive systems, devices andmethods for delivering energy to tissue for a wide variety ofapplications, including medical procedures (e.g., tissue ablation,resection, cautery, vascular thrombosis, treatment of cardiacarrhythmias and dysrhythmias, electrosurgery, tissue harvest, etc.). Incertain embodiments, systems, devices, and methods are provided fortreating a tissue region (e.g., a tumor) through application of energy.

BACKGROUND

Ablation is an important therapeutic strategy for treating certaintissues such as benign and malignant tumors, cardiac arrhythmias,cardiac dysrhythmias and tachycardia. Most approved ablation systemsutilize radio frequency (RF) energy as the ablating energy source.Accordingly, a variety of RF based catheters and power supplies arecurrently available to physicians. However, RF energy has severallimitations, including the rapid dissipation of energy in surfacetissues resulting in shallow “burns” and failure to access deeper tumoror arrhythmic tissues. Another limitation of RF ablation systems is thetendency of eschar and clot formation to form on the energy emittingelectrodes which limits the further deposition of electrical energy.

Microwave energy is an effective energy source for heating biologicaltissues and is used in such applications as, for example, cancertreatment and preheating of blood prior to infusions. Accordingly, inview of the drawbacks of the traditional ablation techniques, there hasrecently been a great deal of interest in using microwave energy as anablation energy source. The advantage of microwave energy over RF is thedeeper penetration into tissue, insensitivity to charring, lack ofnecessity for grounding, more reliable energy deposition, faster tissueheating, and the capability to produce much larger thermal lesions thanRF, which greatly simplifies the actual ablation procedures.Accordingly, there are a number of devices under development thatutilize electromagnetic energy in the microwave frequency range as theablation energy source (see, e.g., U.S. Pat. Nos. 4,641,649, 5,246,438,5,405,346, 5,314,466, 5,800,494, 5,957,969, 6,471,696, 6,878,147, and6,962,586; each of which is herein incorporated by reference in theirentireties).

Unfortunately, current devices configured to deliver microwave energyhave drawbacks. For example, current devices produce relatively smalllesions because of practical limits in power and treatment time. Currentdevices have power limitations in that the power carrying capacity ofthe feedlines are small. Larger diameter feedlines are undesirable,however, because they are less easily inserted percutaneously and mayincrease procedural complication rates. Microwave devices are alsolimited to single antennas for most purposes thus limiting the abilityto simultaneously treat multiple areas or to place several antennas inclose proximity to create large zones of tissue heating. In addition,heating of the feedline at high powers can lead to burns around the areaof insertion for the device.

Improved systems and devices for delivering energy to a tissue regionare needed. In addition, improved systems and devices capable ofdelivering microwave energy without corresponding microwave energy lossare needed. In addition, systems and devices capable of percutaneousdelivery of microwave energy to a subject's tissue without undesiredtissue burning are needed. Furthermore, systems for delivery of desiredamounts of microwave energy without requiring physically large invasivecomponents are needed.

SUMMARY OF THE INVENTION

The present invention relates to comprehensive single and multipleantenna systems, devices and methods for delivering energy to tissue fora wide variety of applications, including medical procedures (e.g.,tissue ablation, resection, cautery, vascular thrombosis, treatment ofcardiac arrhythmias and dysrhythmias, electrosurgery, tissue harvest,etc.). In certain embodiments, systems, devices, and methods areprovided for treating a tissue region (e.g., a tumor) throughapplication of energy.

The present invention provides systems, devices, and methods that employcomponents for the delivery of energy to a tissue region (e.g., tumor,lumen, organ, etc.). In some embodiments, the system comprises an energydelivery device and one or more of: a processor, a power supply, a powersplitter, an imaging system, a tuning system, and a temperatureadjustment system.

The present invention is not limited to a particular type of energydelivery device. The present invention contemplates the use of any knownor future developed energy delivery device in the systems of the presentinvention. In some embodiments, existing commercial energy deliverydevices are utilized. In other embodiments, improved energy deliverydevices having an optimized characteristic (e.g., small size, optimizedenergy delivery, optimized impedance, optimized heat dissipation, etc.)are used. In some such embodiments, the energy delivery device isconfigured to deliver energy (e.g., microwave energy) to a tissueregion. In some embodiments, the energy delivery devices are configuredto deliver microwave energy at an optimized characteristic impedance(e.g., configured to operate with a characteristic impedance higher than50Ω) (e.g., between 50 and 90Ω; e.g., higher than 50, . . . , 55, 56,57, 58, 59, 60, 61, 62, . . . 90Ω, preferably at 77Ω) (see, e.g., U.S.patent application Ser. No. 11/728,428; herein incorporated by referencein its entirety).

A significant source of undesired overheating of the device is thedielectric heating of the insulator, potentially resulting in tissuedamage. The energy delivery devices of the present invention aredesigned to prevent undesired device overheating. The energy deliverydevices are not limited to a particular manner of preventing undesireddevice heating. In some embodiments, the devices employ circulation ofcoolant. In some embodiments, the devices are configured to detect anundesired rise in temperature within the device (e.g., along the outerconductor) and automatically or manually reduce such an undesiredtemperature rise through flowing of coolant through the coolant passagechannels.

In some embodiments, the energy delivery devices have improved coolingcharacteristics. For example, in some embodiments, the devices permitthe use of coolant without increasing the diameter of the device. Thisis in contrast to existing devices that flow coolant through an externalsleeve or otherwise increase the diameter of the device to accommodatethe flow of a coolant. In some embodiments, the energy delivery deviceshave therein one or more coolant passage channels for purposes ofreducing unwanted heat dissipation (see, e.g., U.S. patent applicationSer. No. 11/728,460; herein incorporated by reference in its entirety).In some embodiments, the energy delivery devices have therein a tube(e.g., needle, plastic tube, etc.) that runs the length of or partiallyruns the length of the device, designed to prevent device overheatingthrough circulation of coolant material. In some embodiments, channelsor tubes displace material from a dielectric component located betweenthe inner and outer conductors of a coaxial cable. In some embodiments,channels or tubes replace the dielectric material or substantiallyreplace the dielectric material. In some embodiments, channel or tubesdisplace a portion of the outer conductor. For example, in someembodiments, a portion of the outer conductor is removed or shaved offto generate a passageway for the flow of coolant. One such embodimentsis shown in FIG. 12. In this embodiments, a coaxial cable 900 has anouter conductor 910, an inner conductor 920, and a dielectric material930. In this embodiments, a region 940 of the dielectric material isremoved, creating space for coolant flow. The only remaining outerconductor material the circumscribes or substantially circumscribes thecoaxial cable is at distal 950 and proximal 960 end regions. A thinstrip of conductive material 970 connects the distal 950 and proximal960 end regions. In this embodiments, a thin channel 980 is cut from theconductive material at the proximal end region 960 to permit coolantflow into the region where the outer conductive material was removed (orwas manufacture to be absent) 940. The present invention is not limitedby the size or shape of the passageway, so long as coolant can bedelivered. For example, in some embodiments, the passageway is a linearpath that runs the length of the coaxial cable. In some embodiments,spiral channels are employed. In some embodiments, the tube or channeldisplaces or replaces at least a portion of the inner conductor. Forexample, large portions of the inner conductor may be replaced with acoolant channel, leaving only small portions of metal near the proximaland distal ends of the device to permit tuning, wherein the portions areconnected by a thin strip of conducting material. In some embodiments, aregion of interior space is created within the inner or outer conductorto create one or more channels for coolant. For example, the innerconductor may be provided as a hollow tube of conductive material, witha coolant channel provided in the center. In such embodiments, the innerconductor can be used either for inflow or outflow (or both) of coolant.

In some embodiments, where a coolant tube is placed within the device,the tube has multiple channels for intake and outtake of coolant throughthe device. The device is not limited to a particular positioning of thetube (e.g., coolant needle) within the dielectric material. In someembodiments, the tube is positioned along the outside edge of thedielectric material, the middle of the dielectric material, or at anylocation within the dielectric material. In some embodiments, thedielectric material is pre-formed with a channel designed to receive andsecure the tube. In some embodiments, a handle is attached with thedevice, wherein the handle is configured to, for example, control thepassing of coolant into and out of the tube. In some embodiments, thetube is flexible. In some embodiments, the tube is inflexible. In someembodiments, the portions of the tube are flexible, while other portionsare inflexible. In some embodiments, the tube is compressible. In someembodiments, the tube is incompressible. In some embodiments, portionsof the tube are compressible, while other portions are incompressible.The tube is not limited to a particular shape or size. In someembodiments, wherein the tube is a coolant needle (e.g., a 29 gaugeneedle or equivalent size) that fits within a coaxial cable having adiameter equal or less than a 12 gauge needle. In some embodiments, theexterior of the tube has a coating of adhesive and/or grease so as tosecure the tube or permit sliding movement within the device. In someembodiments, the tube has one or more holes along its length that permitrelease of coolant into desired regions of the device. In someembodiments, the holes are initially blocked with a meltable material,such that a particular threshold of heat is required to melt thematerial and release coolant through the particular hole or holesaffected. As such, coolant is only released in areas that have reachedthe threshold head level.

In some embodiments, coolant is preloaded into the antenna, handle orother component of the devices of the present invention. In otherembodiments, the coolant is added during use. In some pre-loadedembodiments, a liquid coolant is preloaded into, for example, the distalend of the antenna under conditions that create a self-perpetuatingvacuum. In some such embodiments, as the liquid coolant vaporizes, morefluid is drawn in by the vacuum.

The present invention is not limited by the nature of the coolantmaterial employed. Coolants included, but are not limited to, liquidsand gasses. Exemplary coolant fluids include, but are not limited to,one or more of or combinations of, water, glycol, air, inert gasses,carbon dioxide, nitrogen, helium, sulfur hexafluoride, ionic solutions(e.g., sodium chloride with or without potassium and other ions),dextrose in water, Ringer's lactate, organic chemical solutions (e.g.,ethylene glycol, diethylene glycol, or propylene glycol), oils (e.g.,mineral oils, silicone oils, fluorocarbon oils), liquid metals, freons,halomethanes, liquified propane, other haloalkanes, anhydrous ammonia,sulfur dioxide. In some embodiments, cooling occurs, at least in part,by changing concentrations of coolant, pressure, or volume. For example,cooling can be achieved via gas coolants using the Joule-Thompsoneffect. In some embodiments, the cooling is provided by a chemicalreaction. The devices are not limited to a particular type oftemperature reducing chemical reaction. In some embodiments, thetemperature reducing chemical reaction is an endothermic reaction. Thedevices are not limited to a particular manner of applying endothermicreactions for purposes of preventing undesired heating. In someembodiments, first and second chemicals are flowed into the device suchthat they react to reduce the temperature of the device. In someembodiments, the device is prepared with the first and second chemicalspreloaded in the device. In some embodiments, the chemicals areseparated by a barrier that is removed when desired. In someembodiments, the barrier is configured to melt upon exposure to apredetermined temperature or temperature range. In such embodiments, thedevice initiates the endothermical reaction only upon reaching a heatlevel that merits cooling. In some embodiments, multiple differentbarriers are located throughout the device such that local coolingoccurs only at those portions of the device where undesired heating isoccurring. In some embodiment, the barriers used are beads thatencompass one of the two chemicals. In some embodiments, the barriersare walls (e.g., discs in the shape of washers) that melt to combine thetwo chemicals. In some embodiments, the barriers are made of wax that isconfigured to melt at a predetermined temperature. The devices are notlimited to a particular type, kind or amount of meltable material. Insome embodiments, the meltable material is biocompatible. The devicesare not limited to a particular type, kind, or amount of first andsecond chemicals, so long as their mixture results in a temperaturereducing chemical reaction. In some embodiments, the first materialincludes barium hydroxide octahydrate crystals and the second materialis dry ammonium chloride. In some embodiments, the first material iswater and the second material is ammonium chloride. In some embodiments,the first material is thionyl chloride (SOCl₂) and the second materialis cobalt(II) sulfate heptahydrate. In some embodiments, the firstmaterial is water and the second material is ammonium nitrate. In someembodiments, the first material is water and the second material ispotassium chloride. In some embodiments, the first material is ethanolicacid and the second material is sodium carbonate. In some embodiments, ameltable material is used that, itself, reduces heat by melting anflowing in a manner such that the heat at the outer surface of thedevice is reduced.

In some embodiments, the energy delivery devices prevent undesiredheating and/or maintain desired energy delivery properties throughadjusting the amount of energy emitted from the device (e.g., adjustingthe energy wavelength resonating from the device) as temperaturesincrease. The devices are not limited to a particular method ofadjusting the amount of energy emitted from the device. In someembodiments, the devices are configured such that as the device reachesa certain threshold temperature or as the device heats over a range, theenergy wavelength resonating from the device is adjusted. The devicesare not limited to a particular method for adjusting energy wavelengthresonating from the device. In some embodiments, the device has thereina material that changes in volume as the temperature increases. Thechange in volume is used to move or adjust a component of the devicethat affects energy delivery. For example, in some embodiments, amaterial is used that expands with increasing temperature. The expansionis used to move the distal tip of the device outward (increasing itsdistance from the proximal end of the device), altering the energydelivery properties of the device. This finds particular use with thecenter-fed dipole embodiments of the present invention.

In certain embodiments, the present invention provides a devicecomprising an antenna configured for delivery of energy to a tissue,wherein a distal end of the antenna comprises a center-fed dipolecomponent comprising a rigid hollow tube encompassing a conductor,wherein a stylet is secured within the hollow tube. In some embodiments,the hollow tube has a diameter equal to or less than a 20-gauge needle.In some embodiments, the hollow tube has a diameter equal to or lessthan a 17-gauge needle. In some embodiments, the hollow tube has adiameter equal to or less than a 12-gauge needle. In some embodiments,the device further comprises a tuning element for adjusting the amountof energy delivered to the tissue. In some embodiments, the device isconfigured to deliver a sufficient amount of energy to ablate the tissueor cause thrombosis. In some embodiments, the conductor extends halfwaythrough the hollow tube. In some embodiments, the hollow tube has alength λ/2, wherein λ is the electromagnetic field wavelength in themedium of the tissue. In some embodiments, an expandable material ispositioned near the stylet such that as the device increases intemperature the expandable material expands and pushes onto the styletmoving the stylet and changes the energy delivery properties of thedevice. In some embodiments, the expandable material is positionedbehind (proximal to) a metal disc that provides the resonant element forthe center-fed dipole device. As the material expands, the disc ispushed distally, adjusting the tuning of the device. The expandablematerial is preferably selected so that the rate of expansion coincideswith a desired change in energy delivery for optimal results. However,it should be understood that any change in the desired directions findsuse with the invention. In some embodiments, the expandable material iswax.

In some embodiments, the device has a handle attached with the device,wherein the handle is configured to, for example, control the passing ofcoolant into and out of coolant channels. In some embodiments, only thehandle is cooled. In other embodiments, the handle and an attachedantenna are cooled. In some embodiments, the handle automatically passescoolant into and out of the coolant channels after a certain amount oftime and/or as the device reaches a certain threshold temperature. Insome embodiments, the handle automatically stops passage of coolant intoand out of the coolant channels after a certain amount of time and/or asthe temperature of the device drops below a certain thresholdtemperature. In some embodiments, coolant flowed through the handle ismanually controlled.

In some embodiments, the energy delivery devices have therein a centerfed dipole component (see, e.g., U.S. patent application Ser. No.11/728,457; herein incorporated by reference in its entirety). In someembodiments, the energy delivery devices comprise a catheter withmultiple segments for transmitting and emitting energy (see, e.g., U.S.patent application Ser. Nos. 11/237,430, 11/237,136, and 11/236,985;each herein incorporated by reference in their entireties). In someembodiments, the energy delivery devices comprise a triaxial microwaveprobe with optimized tuning capabilities to reduce reflective heat loss(see, e.g., U.S. Pat. No. 7,101,369; see, also, U.S. patent applicationSer. Nos. 10/834,802, 11/236,985, 11/237,136, 11,237,430, 11/440,331,11/452,637, 11/502,783, 11/514,628; and International Patent ApplicationNo. PCT/US05/14534; herein incorporated by reference in its entirety).In some embodiments, the energy delivery devices emit energy through acoaxial transmission line (e.g., coaxial cable) having air or othergases as a dielectric core (see, e.g., U.S. patent application Ser. No.11/236,985; herein incorporated by reference in its entirety). In somesuch embodiments, materials that support the structure of the devicebetween the inner and outer conductors may be removed prior to use. Forexample, in some embodiments, the materials a made of a dissolvable ormeltable material that is remove prior to or during use. In someembodiments, the materials are meltable and are removed during use (uponexposure to heat) so as to optimize the energy delivery properties ofthe device over time (e.g., in response to temperature changes intissue, etc.).

The present invention is not limited to a particular coaxialtransmission line shape. Indeed, in some embodiments, the shape of thecoaxial transmission line and/or the dielectric element is adjustable tofit a particular need. In some embodiments, the cross-sectional shape ofthe coaxial transmission line and/or the dielectric element is circular.In some embodiments, the cross-sectional shape is non-circular (e.g.,oval, etc.). Such shapes may apply to the coaxial cable as a whole, ormay apply to one or more sub-components only. For example, an ovaldielectric material may be placed in a circular outer conductor. This,for example, has the advantage of creating two channels that may beemployed, for example, to circulate coolant. As another example,square/rectangular dielectric material may be placed in a circular outconductor. This, for example, has the advantage of creating fourchannels. Different polygonal shapes in the cross-section (e.g.,pentagon, hexagon, etc.) may be employed to create different numbers andshapes of channels. The cross-sectional shape need not be the samethroughout the length of the cable. In some embodiments, a first shapeis used for a first region (e.g., a proximal region) of the cable and asecond shape is used for a second region (e.g., a distal region) of thecable. Irregular shapes may also be employed. For example, a dielectricmaterial having an indented groove running its length may be employed ina circular outer conductor to create a single channel of any desiredsize and shape. In some embodiments, the channel provides space forfeeding coolant, a needle, or other desired components into the devicewithout increasing the ultimate outer diameter of the device.

Likewise, in some embodiments, an antenna of the present invention has anon-circular cross-sectional shape along its length or for one or moresubsections of its length. In some embodiments, the antenna isnon-cylindrical, but contains a coaxial cable that is cylindrical. Inother embodiments, the antenna is non-cylindrical and contains a coaxialcable that is non-cylindrical (e.g., matching the shape of the antennaor having a different non-cylindrical shape). In some embodiments,having any one or more components (e.g., cannula, outer shell ofantenna, outer conductor of coaxial cable, dielectric material ofcoaxial cable, inner conductor of coaxial cable) possessing anon-cylindrical shape permits the creation of one or more channels inthe device that may be used, among other reasons, to circulate coolant.Non-circular shapes, particularly in the outer diameter of the antennaalso find use for certain medical or other applications. For example, ashape may be chosen to maximize flexibility or access to particularinner body locations. Shape may also be chose to optimize energydelivery. Shape (e.g., non-cylindrical shape) may also be selected tomaximize rigidity and/or strength of the device, particularly for smalldiameter devices.

In certain embodiments, the present invention provides a devicecomprising an antenna, wherein the antenna comprises an outer conductorenveloped around an inner conductor, wherein the inner conductor isdesigned to receive and transmit energy, wherein the outer conductor hastherein at least one gap positioned circumferentially along the outerconductor, wherein multiple energy peaks are generated along the lengthof the antenna, the position of the energy peaks controlled by thelocation of the gap. In some embodiments, the energy is microwave energyand/or radiofrequency energy. In some embodiments, the outer conductorhas therein two of the gaps. In some embodiments, the antenna comprisesa dielectric layer disposed between the inner conductor and the outerconductor. In some embodiments, the dielectric layer has near-zeroconductivity. In some embodiments, the device further comprises astylet. In some embodiments, the inner conductor has a diameter ofapproximately 0.013 inches or less.

In some embodiments, any gaps or inconsistencies or irregularities inthe outer conductor or outer surface of the device are filled with amaterial to provide a smooth, even, or substantially smooth, even outersurface. In some embodiments, a heat-resistant, resin is used to fillgaps, inconsistencies, and/or irregularities. In some embodiments, theresin is biocompatible. In other embodiments, it is not biocompatible,but, for example, can be coated with a biocompatible material. In someembodiments, the resin is configurable to any desired size or shape. Assuch, the resin, when hardened, may be used to provide a sharp stylettip to the devices or any other desired physical shape.

In some embodiments, the device comprises a sharp stylet tip. The tipmay be made of any material. In some embodiments, the tip is made fromhardened resin. In some embodiments, the tip is metal. In some suchembodiments, the metal tip is an extension of a metal portion of anantenna and is electrically active.

In some embodiments, the energy delivery devices are configured todelivery energy to a tissue region within a system comprising aprocessor, a power supply, a power splitter with the capability ofindividual control of power delivery to each antenna, an imaging system,a tuning system, and/or a temperature adjustment system.

The present invention is not limited to a particular type of processor.In some embodiments, the processor is designed to, for example, receiveinformation from components of the system (e.g., temperature monitoringsystem, energy delivery device, tissue impedance monitoring component,etc.), display such information to a user, and manipulate (e.g.,control) other components of the system. In some embodiments, theprocessor is configured to operate within a system comprising an energydelivery device, a power supply, a power splitter, an imaging system, atuning system, and/or a temperature adjustment system.

The present invention is not limited to a particular type of powersupply. In some embodiments, the power supply is configured to provideany desired type of energy (e.g., microwave energy, radiofrequencyenergy, radiation, cryo energy, electroporation, high intensity focusedultrasound, and/or mixtures thereof). In some embodiments, the powersupply utilizes a power splitter to permit delivery of energy to two ormore energy delivery devices. In some embodiments, the power supply isconfigured to operate within a system comprising a power splitter, aprocessor, an energy delivery device, an imaging system, a tuningsystem, and/or a temperature adjustment system.

The present invention is not limited to a particular type of imagingsystem. In some embodiments, the imaging system utilizes imaging devices(e.g., endoscopic devices, stereotactic computer assisted neurosurgicalnavigation devices, thermal sensor positioning systems, motion ratesensors, steering wire systems, intraprocedural ultrasound, fluoroscopy,computerized tomography magnetic resonance imaging, nuclear medicineimaging devices triangulation imaging, thermoacoustic imaging, infraredand/or laser imaging, electromagnetic imaging) (see, e.g., U.S. Pat.Nos. 6,817,976, 6,577,903, and 5,697,949, 5,603,697, and InternationalPatent Application No. WO 06/005,579; each herein incorporated byreference in their entireties). In some embodiments, the systems utilizeendoscopic cameras, imaging components, and/or navigation systems thatpermit or assist in placement, positioning, and/or monitoring of any ofthe items used with the energy systems of the present invention. In someembodiments, the imaging system is configured to provide locationinformation of particular components of the energy delivery system(e.g., location of the energy delivery device). In some embodiments, theimaging system is configured to operate within a system comprising aprocessor, an energy delivery device, a power supply, a tuning system,and/or a temperature adjustment system.

The present invention is not limited to a particular tuning system. Insome embodiments, the tuning system is configured to permit adjustmentof variables (e.g., amount of energy delivered, frequency of energydelivered, energy delivered to one or more of a plurality of energydevices that are provided in the system, amount of or type of coolantprovided, etc.) within the energy delivery system. In some embodiments,the tuning system comprises a sensor that provides feedback to the useror to a processor that monitors the function of an energy deliverydevice continuously or at time points. The sensor may record and/orreport back any number of properties, including, but not limited to,heat at one or more positions of a components of the system, heat at thetissue, property of the tissue, and the like. The sensor may be in theform of an imaging device such as CT, ultrasound, magnetic resonanceimaging, fluoroscopy, nuclear medicine imaging, or any other imagingdevice. In some embodiments, particularly for research application, thesystem records and stores the information for use in future optimizationof the system generally and/or for optimization of energy delivery underparticular conditions (e.g., patient type, tissue type, size and shapeof target region, location of target region, etc.). In some embodiments,the tuning system is configured to operate within a system comprising aprocessor, an energy delivery device, a power supply, an imaging, and/ora temperature adjustment system. In some embodiments, the imaging orother control components provide feedback to the ablation device so thatthe power output (or other control parameter) can be adjusted to providean optimum tissue response.

The present invention is not limited to a particular temperatureadjustment system. In some embodiments, the temperature adjustmentsystems are designed to reduce unwanted heat of various components ofthe system (e.g., energy delivery devices) during medical procedures(e.g., tissue ablation) or keep the target tissue within a certaintemperature range. In some embodiments, the temperature adjustmentsystems are configured to operate within a system comprising aprocessor, an energy delivery device, a power supply, a power splitter,a tuning system, and/or an imaging system.

In some embodiments, the systems further comprise temperature monitoringor reflected power monitoring systems for monitoring the temperature orreflected power of various components of the system (e.g., energydelivery devices) and/or a tissue region. In some embodiments, themonitoring systems are designed to alter (e.g., prevent, reduce) thedelivery of energy to a particular tissue region if, for example, thetemperature or amount of reflected energy, exceeds a predeterminedvalue. In some embodiments, the temperature monitoring systems aredesigned to alter (e.g., increase, reduce, sustain) the delivery ofenergy to a particular tissue region so as to maintain the tissue orenergy delivery device at a preferred temperature or within a preferredtemperature range.

In some embodiments, the systems further comprise an identification ortracking system configured, for example, to prevent the use ofpreviously used components (e.g., non-sterile energy delivery devices),to identify the nature of a component of the system so the othercomponents of the system may be appropriately adjusted for compatibilityor optimized function. In some embodiments, the system reads a bar codeor other information-conveying element associated with a component ofthe systems of the invention.

The present invention is not limited by the type of components used inthe systems or the uses employed. Indeed, the devices may be configuredin any desired manner. Likewise, the systems and devices may be used inany application where energy is to be delivered. Such uses include anyand all medical, veterinary, and research applications. However, thesystems and devices of the present invention may be used in agriculturalsettings, manufacturing settings, mechanical settings, or any otherapplication where energy is to be delivered.

In some embodiments, the systems are configured for percutaneous,intravascular, intracardiac, laparoscopic, or surgical delivery ofenergy. In some embodiments, the systems are configured for delivery ofenergy to a target tissue or region. The present invention is notlimited by the nature of the target tissue or region. Uses include, butare not limited to, treatment of heart arrhythmia, tumor ablation(benign and malignant), control of bleeding during surgery, aftertrauma, for any other control of bleeding, removal of soft tissue,tissue resection and harvest, treatment of varicose veins, intraluminaltissue ablation (e.g., to treat esophageal pathologies such as Barrett'sEsophagus and esophageal adenocarcinoma), treatment of bony tumors,normal bone, and benign bony conditions, intraocular uses, uses incosmetic surgery, treatment of pathologies of the central nervous systemincluding brain tumors and electrical disturbances, sterilizationprocedures (e.g., ablation of the fallopian tubes) and cauterization ofblood vessels or tissue for any purposes. In some embodiments, thesurgical application comprises ablation therapy (e.g., to achievecoagulative necrosis). In some embodiments, the surgical applicationcomprises tumor ablation to target, for example, metastatic tumors. Insome embodiments, the device is configured for movement and positioning,with minimal damage to the tissue or organism, at any desired location,including but not limited to, the brain, neck, chest, abdomen, andpelvis. In some embodiments, the systems are configured for guideddelivery, for example, by computerized tomography, ultrasound, magneticresonance imaging, fluoroscopy, and the like.

In certain embodiments, the present invention provides methods oftreating a tissue region, comprising: providing a tissue region and asystem described herein (e.g., an energy delivery device, and at leastone of the following components: a processor, a power supply, a powersplitter, a temperature monitor, an imager, a tuning system, and/or atemperature reduction system); positioning a portion of the energydelivery device in the vicinity of the tissue region, and delivering anamount of energy with the device to the tissue region. In someembodiments, the tissue region is a tumor. In some embodiments, thedelivering of the energy results in, for example, the ablation of thetissue region and/or thrombosis of a blood vessel, and/orelectroporation of a tissue region. In some embodiments, the tissueregion is a tumor. In some embodiments, the tissue region comprises oneor more of the heart, liver, genitalia, stomach, lung, large intestine,small intestine, brain, neck, bone, kidney, muscle, tendon, bloodvessel, prostate, bladder, and spinal cord. In some embodiments, theprocessor receives information from sensors and monitors and controlsthe other components of the systems. In some embodiments, the energyoutput of the power supply is altered, as desired, for optimizedtherapy. In some embodiments, where more than one energy deliverycomponent is provided, the amount of energy delivered to each of thedelivery components is optimized to achieve the desired result. In someembodiments, the temperature of the system is monitored by a temperaturesensor and, upon reaching or approaching a threshold level, is reducedby activation of the temperature reduction system. In some embodimentsthe imaging system provides information to the processor, which isdisplayed to a user of the system and may be used in a feedback loop tocontrol the output of the system.

In some embodiments, energy is delivered to the tissue region indifferent intensities and from different locations within the device.For example, certain regions of the tissue region may be treated throughone portion of the device, while other regions of the tissue may betreated through a different portion of the device. In addition, two ormore regions of the device may simultaneously deliver energy to aparticular tissue region so as to achieve constructive phaseinterference (e.g., wherein the emitted energy achieves a synergisticeffect). In other embodiments, two or more regions of the device maydeliver energy so as to achieve a destructive interference effect. Insome embodiments, the method further provides additional devices forpurposes of achieving constructive phase interference and/or destructivephase interference. In some embodiments, phase interference (e.g.,constructive phase interference, destructive phase interference),between one or more devices, is controlled by a processor, a tuningelement, a user, and/or a power splitter.

The systems, devices, and methods of the present invention may be usedin conjunction with other systems, device, and methods. For example, thesystems, devices, and methods of the present invention may be used withother ablation devices, other medical devices, diagnostic methods andreagents, imaging methods and reagents, and therapeutic methods andagents. Use may be concurrent or may occur before or after anotherintervention. The present invention contemplates the use systems,devices, and methods of the present invention in conjunction with anyother medical interventions.

Additionally, integrated ablation and imaging systems are needed thatprovide feedback to a user and permit communication between varioussystem components. System parameters may be adjusted during the ablationto optimize energy delivery. In addition, the user is able to moreaccurately determine when the procedure is successfully completed,reducing the likelihood of unsuccessful treatments and/or treatmentrelated complications.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic view of an energy delivery system in anembodiment of the invention.

FIG. 2 shows various shapes of coaxial transmission lines and/or thedielectric elements in some embodiments of the present invention.

FIGS. 3A and 3B display a coaxial transmission line embodiment havingpartitioned segments with first and second materials blocked by meltablewalls for purposes of preventing undesired device heating (e.g., heatingalong the outer conductor).

FIGS. 4A and 4B display a coaxial transmission line embodiment havingpartitioned segments segregated by meltable walls containing first andsecond materials (e.g., materials configured to generate a temperaturereducing chemical reaction upon mixing) preventing undesired deviceheating (e.g., heating along the outer conductor).

FIG. 5 shows a schematic drawing of a handle configured to control thepassing of coolant into and out of the coolant channels.

FIG. 6 shows a transverse cross-section schematic of coaxial cableembodiments having coolant passages.

FIG. 7 shows a coolant circulating tube (e.g., coolant needle, catheter)positioned within an energy emission device having an outer conductorand a dielectric material.

FIG. 8 schematically shows the distal end of a device (e.g., antenna ofan ablation device) of the present invention that comprises a center feddipole component of the present invention.

FIG. 9 shows the test setup and position of temperature measurementstations. As shown, the ablation needle shaft for all experiments was20.5 cm. Probes 1, 2 and 3 were located 4, 8 and 12 cm proximal to thetip of the stainless needle.

FIG. 10 shows treatment at 35% (microwaves “on” from 13:40 to 13:50)with anomalously high (6.5%) reflected power. Probe 3 was initiallyplaced just outside of the liver tissue, in air.

FIG. 11 shows 10 minute treatment at 45% (microwaves on from 14:58 to15:08) with anomalously high (6.5%) reflected power. Peak temperature atStation 4 was 40.25° C.

FIG. 12 shows one a coaxial cable having a region of its outer conductorremoved to create space for coolant flow in one embodiment of thepresent invention.

FIG. 13 shows a schematic view of an import/export box, a transportsheath, and a procedure device hub.

DETAILED DESCRIPTION

The present invention relates to comprehensive systems, devices andmethods for delivering energy (e.g., microwave energy, radiofrequencyenergy) to tissue for a wide variety of applications, including medicalprocedures (e.g., tissue ablation, resection, cautery, vascularthrombosis, intraluminal ablation of a hollow viscus, cardiac ablationfor treatment of arrhythmias, electrosurgery, tissue harvest, cosmeticsurgery, intraocular use, etc.). In particular, the present inventionprovides systems for the delivery of microwave energy comprising a powersupply, a power splitter, a processor, an energy emitting device, acooling system, an imaging system, a temperature monitoring system,and/or a tracking system. In certain embodiments, systems, devices, andmethods are provided for treating a tissue region (e.g., a tumor)through use of the energy delivery systems of the present invention.

The systems of the present invention may be combined within varioussystem/kit embodiments. For example, the present invention providessystems comprising one or more of a generator, a power distributionsystem, a power splitter, an energy applicator, along with any one ormore accessory component (e.g., surgical instruments, software forassisting in procedure, processors, temperature monitoring devices,etc.). The present invention is not limited to any particular accessorycomponent.

The systems of the present invention may be used in any medicalprocedure (e.g., percutaneous or surgical) involving delivery of energy(e.g., radiofrequency energy, microwave energy, laser, focusedultrasound, etc.) to a tissue region. The systems are not limited totreating a particular type or kind of tissue region (e.g., brain, liver,heart, blood vessels, foot, lung, bone, etc.). For example, the systemsof the present invention find use in ablating tumor regions. Additionaltreatments include, but are not limited to, treatment of heartarrhythmia, tumor ablation (benign and malignant), control of bleedingduring surgery, after trauma, for any other control of bleeding, removalof soft tissue, tissue resection and harvest, treatment of varicoseveins, intraluminal tissue ablation (e.g., to treat esophagealpathologies such as Barrett's Esophagus and esophageal adenocarcinoma),treatment of bony tumors, normal bone, and benign bony conditions,intraocular uses, uses in cosmetic surgery, treatment of pathologies ofthe central nervous system including brain tumors and electricaldisturbances, sterilization procedures (e.g., ablation of the fallopiantubes) and cauterization of blood vessels or tissue for any purposes. Insome embodiments, the surgical application comprises ablation therapy(e.g., to achieve coagulative necrosis). In some embodiments, thesurgical application comprises tumor ablation to target, for example,primary or metastatic tumors. In some embodiments, the surgicalapplication comprises the control of hemorrhage (e.g. electrocautery).In some embodiments, the surgical application comprises tissue cuttingor removal. In some embodiments, the device is configured for movementand positioning, with minimal damage to the tissue or organism, at anydesired location, including but not limited to, the brain, neck, chest,abdomen, pelvis, and extremities. In some embodiments, the device isconfigured for guided delivery, for example, by computerized tomography,ultrasound, magnetic resonance imaging, fluoroscopy, and the like.

The illustrated embodiments provided below describe the systems of thepresent invention in terms of medical applications (e.g., ablation oftissue through delivery of microwave energy). However, it should beappreciated that the systems of the present invention are not limited tomedical applications. The systems may be used in any setting requiringdelivery of energy to a load (e.g., agricultural settings, manufacturesettings, research settings, etc.). The illustrated embodiments describethe systems of the present invention in terms of microwave energy. Itshould be appreciated that the systems of the present invention are notlimited to a particular type of energy (e.g., radiofrequency energy,microwave energy, focused ultrasound energy, laser, plasma).

The systems of the present invention are not limited to any particularcomponent or number of components. In some embodiments, the systems ofthe present invention include, but are not limited to including, a powersupply, a power splitter, a processor, an energy delivery device with anantenna, a cooling system, an imaging system, and/or a tracking system.When multiple antennas are in use, the system may be used toindividually control each antenna separately.

FIG. 1 shows an exemplary system of the invention. As shown, the energydelivery system comprises a power supply, a transmission line, a powerdistribution component (e.g., power splitter), a processor, an imagingsystem, a temperature monitoring system and an energy delivery device.In some embodiments, as shown, the components of the energy deliverysystems are connected via a transmission line, cables, etc. In someembodiments, the energy delivery device is separated from the powersupply, power splitter, processor, imaging system, temperaturemonitoring system across a sterile field barrier.

Exemplary components of the energy delivery systems are described inmore detail in the following sections: I. Power Supply; II. Energydelivery devices; III. Processor; IV. Imaging Systems; V. TuningSystems; VI. Temperature Adjustment Systems; VII. IdentificationSystems; VIII. Temperature Monitoring Devices; and IX. Uses.

I. Power Supply

The energy utilized within the energy delivery systems of the presentinvention is supplied through a power supply. The present invention isnot limited to a particular type or kind of power supply. In someembodiments, the power supply is configured to provide energy to one ormore components of the energy delivery systems of the present invention(e.g., ablation devices). The power supply is not limited to providing aparticular type of energy (e.g., radiofrequency energy, microwaveenergy, radiation energy, laser, focused ultrasound, etc.). The powersupply is not limited to providing particular amounts of energy or at aparticular rate of delivery. In some embodiments, the power supply isconfigured to provide energy to an energy delivery device for purposesof tissue ablation.

The present invention is not limited to a particular type of powersupply. In some embodiments, the power supply is configured to provideany desired type of energy (e.g., microwave energy, radiofrequencyenergy, radiation, cryo energy, electroporation, high intensity focusedultrasound, and/or mixtures thereof). In some embodiments, the type ofenergy provided with the power supply is microwave energy. In some someembodiments, the power supply provides microwave energy to ablationdevices for purposes of tissue ablation. The use of microwave energy inthe ablation of tissue has numerous advantages. For example, microwaveshave a broad field of power density (e.g., approximately 2 cmsurrounding an antenna depending on the wavelength of the appliedenergy) with a correspondingly large zone of active heating, therebyallowing uniform tissue ablation both within a targeted zone and inperivascular regions (see, e.g., International Publication No. WO2006/004585; herein incorporated by reference in its entirety). Inaddition, microwave energy has the ability to ablate large or multiplezones of tissue using multiple probes with more rapid tissue heating.Microwave energy has an ability to penetrate tissue to create deeplesions with less surface heating. Energy delivery times are shorterthan with radiofrequency energy and probes can heat tissue sufficientlyto create an even and symmetrical lesion of predictable and controllabledepth. Microwave energy is generally safe when used near vessels. Also,microwaves do not rely on electrical conduction as it radiates throughtissue, fluid/blood, as well as air. Therefore, microwave energy can beused in tissue, lumens, lungs, and intravascularly.

In some embodiments, the power supply is an energy generator. In someembodiments, the generator is configured to provide as much as 100 wattsof microwave power of a frequency of from 915 MHz to 2.45 GHz, althoughthe present invention is not so limited. Solid state microwavegenerators in the 1-3 GHz range are very expensive. Therefore, in someembodiments, a conventional magnetron of the type commonly used inmicrowave ovens is chosen as the generator. It should be appreciated,however, that any other suitable microwave power source can substitutedin its place. In some embodiments, the types of generators include, butare not limited to, those available from Cober-Muegge, LLC, Norwalk,Conn., USA, Sairem generators, and Gerling Applied Engineeringgenerators. In some embodiments, the generator has at leastapproximately 60 Watts available (e.g., 50, 55, 56, 57, 58, 59, 60, 61,62, 65, 70, 100, 500, 1000 Watts). For a higher-power operation, thegenerator is able to provide approximately 300 Watts (e.g., 200 Watts,280, 290, 300, 310, 320, 350, 400, 750 Watts). In some embodiments,wherein multiple antennas are used, the generator is able to provide asmuch energy as necessary (e.g., 400 Watts, 500, 750, 1000, 2000, 10,000Watts).

In some embodiments, the power supply distributes energy (e.g.,collected from a generator) with a power distribution system. Thepresent invention is not limited to a particular power distributionsystem. In some embodiments, the power distribution system is configuredto provide energy to an energy delivery device (e.g., a tissue ablationcatheter) for purposes of tissue ablation. The power distribution systemis not limited to a particular manner of collecting energy from, forexample, a generator. The power distribution system is not limited to aparticular manner of providing energy to ablation devices. In someembodiments, the power distribution system is configured to transformthe characteristic impedance of the generator such that it matches thecharacteristic impedance of an energy delivery device (e.g., a tissueablation catheter).

In some embodiments, the power distribution system is configured with avariable power splitter so as to provide varying energy levels todifferent regions of an energy delivery device or to different energydelivery devices (e.g., a tissue ablation catheter). In someembodiments, the power splitter is provided as a separate component ofthe system. In some embodiments, the power splitter is used to feedmultiple energy delivery devices with separate energy signals. In someembodiments, the power splitter electrically isolates the energydelivered to each energy delivery device so that, for example, if one ofthe devices experiences an increased load as a result of increasedtemperature deflection, the energy delivered to that unit is altered(e.g., reduced, stopped) while the energy delivered to alternate devicesis unchanged. The present invention is not limited to a particular typeor kind of power splitter. In some embodiments, the power splitter isdesigned by SM Electronics. In some embodiments, the power splitter isconfigured to receive energy from a power generator and provide energyto additional system components (e.g., energy delivery devices). In someembodiments the power splitter is able to connect with one or moreadditional system components (e.g., 1, 2, 3, 4, 5, 7, 10, 15, 20, 25,50, 100, 500 . . . ). In some embodiments, the power splitter isconfigured to deliver variable amounts of energy to different regionswithin an energy delivery device for purposes of delivering variableamounts of energy from different regions of the device. In someembodiments, the power splitter is used to provide variable amounts ofenergy to multiple energy delivery devices for purposes of treating atissue region. In some embodiments, the power splitter is configured tooperate within a system comprising a processor, an energy deliverydevice, a temperature adjustment system, a power splitter, a tuningsystem, and/or an imaging system. In some embodiments, the powersplitter is able to handle maximum generator outputs plus, for example,25% (e.g., 20%, 30%, 50%). In some embodiments, the power splitter is a1000-watt-rated 2-4 channel power splitter.

In some embodiments, where multiple antennas are employed, the system ofthe present invention may be configured to run them simultaneously orsequentially (e.g., with switching). In some embodiments, the system isconfigured to phase the fields for constructive or destructiveinterference. Phasing may also be applied to different elements within asingle antenna.

II. Energy Delivery Devices

The energy delivery systems of the present invention contemplate the useof any type of device configured to deliver (e.g., emit) energy (e.g.,ablation device, surgical device, etc.) (see, e.g., U.S. Pat. Nos.7,101,369, 7,033,352, 6,893,436, 6,878,147, 6,823,218, 6,817,999,6,635,055, 6,471,696, 6,383,182, 6,312,427, 6,287,302, 6,277,113,6,251,128, 6,245,062, 6,026,331, 6,016,811, 5,810,803, 5,800,494,5,788,692, 5,405,346, 4,494,539, U.S. patent application Ser. Nos.11/728,460, 11/728,457, 11/728,428, 11/237,136, 11/236,985, 10/980,699,10/961,994, 10/961,761, 10/834,802, 10/370,179, 09/847,181; GreatBritain Patent Application Nos. 2,406,521, 2,388,039; European PatentNo. 1395190; and International Patent Application Nos. WO 06/008481, WO06/002943, WO 05/034783, WO 04/112628, WO 04/033039, WO 04/026122, WO03/088858, WO 03/039385 WO 95/04385; each herein incorporated byreference in their entireties). Such devices include any and allmedical, veterinary, and research applications devices configured forenergy emission, as well as devices used in agricultural settings,manufacturing settings, mechanical settings, or any other applicationwhere energy is to be delivered.

In some embodiments, the systems utilize energy delivery devices havingtherein antennae configured to emit energy (e.g., microwave energy,radiofrequency energy, radiation energy). The systems are not limited toparticular types or designs of antennae (e.g., ablation device, surgicaldevice, etc.). In some embodiments, the systems utilize energy deliverydevices having linearly shaped antennae (see, e.g., U.S. Pat. Nos.6,878,147, 4,494,539, U.S. patent application Ser. Nos. 11/728,460,11/728,457, 11/728,428, 10/961,994, 10/961,761; and International PatentApplication No., WO 03/039385; each herein incorporated by reference intheir entireties). In some embodiments, the systems utilize energydelivery devices having non-linearly shaped antennae (see, e.g., U.S.Pat. Nos. 6,251,128, 6,016,811, and 5,800,494, U.S. patent applicationSer. No. 09/847,181, and International Patent Application No. WO03/088858; each herein incorporated by reference in their entireties).In some embodiments, the antennae have horn reflection components (see,e.g., U.S. Pat. Nos. 6,527,768, 6,287,302; each herein incorporated byreference in their entireties). In some embodiments, the antenna has adirectional reflection shield (see, e.g., U.S. Pat. No. 6,312,427;herein incorporated by reference in its entirety). In some embodiments,the antenna has therein a securing component so as to secure the energydelivery device within a particular tissue region (see, e.g., U.S. Pat.Nos. 6,364,876, and 5,741,249; each herein incorporated by reference intheir entireties).

Generally, antennae configured to emit energy comprise coaxialtransmission lines. The devices are not limited to particularconfigurations of coaxial transmission lines. Examples of coaxialtransmission lines include, but are not limited to, coaxial transmissionlines developed by Pasternack, Micro-coax, and SRC Cables. In someembodiments, the coaxial transmission line has a center conductor, adielectric element, and an outer conductor (e.g., outer shield). In someembodiments, the systems utilize antennae having flexible coaxialtransmission lines (e.g., for purposes of positioning around, forexample, pulmonary veins or through tubular structures) (see, e.g., U.S.Pat. Nos. 7,033,352, 6,893,436, 6,817,999, 6,251,128, 5,810,803,5,800,494; each herein incorporated by reference in their entireties).In some embodiments, the systems utilize antennae having rigid coaxialtransmission lines (see, e.g., U.S. Pat. No. 6,878,147, U.S. patentapplication Ser. Nos. 10/961,994, 10/961,761, and International PatentApplication No. WO 03/039385; each herein incorporated by reference intheir entireties).

The present invention is not limited to a particular coaxialtransmission line shape. Indeed, in some embodiments, the shape of thecoaxial transmission line and/or the dielectric element is selectedand/or adjustable to fit a particular need. FIG. 2 shows some of thevarious, non-limiting shapes the coaxial transmission line and/or thedielectric element may assume.

In some embodiments, the outer conductor is a 20-gauge needle or acomponent of similar diameter to a 20-gauge needle. Preferably, forpercutaneous use the outer conductor is not larger than a 16-gaugeneedle (e.g., no larger than an 18-gauge needle). In some embodiments,the outer conductor is a 17-gauge needle. However, in some embodiments,larger devices are used, as desired. For example, in some embodiments, a12-gauge diameter is used. The present invention is not limited by thesize of the outer conductor. In some embodiments, the outer conductor isconfigured to fit within series of larger needles for purposes ofassisting in medical procedures (e.g., assisting in tissue biopsy) (see,e.g., U.S. Pat. Nos. 6,652,520, 6,582,486, 6,355,033, 6,306,132; eachherein incorporated by reference in their entireties). In someembodiments, the center conductor is configured to extend beyond theouter conductor for purposes of delivering energy to a desired location.In some embodiments, some or all of the feedline characteristicimpedance is optimized for minimum power dissipation, irrespective ofthe type of antenna that terminates at its distal end.

In some embodiments, the energy delivery devices are provided with aproximal portion and a distal portion, wherein the distal portion isdetachable and provided in a variety of different configurations thatcan attach to a core proximal portion. For example, in some embodiments,the proximal portion comprises a handle and an interface to othercomponents of the system (e.g., power supply) and the distal portioncomprises a detachable antenna having desired properties. A plurality ofdifferent antenna configured for different uses may be provided andattached to the handle unit for the appropriate indication.

In some embodiments, the device is configured to attach with adetachable handle. The present invention is not limited to a particulartype of detachable handle. In some embodiments, the detachable handle isconfigured to connect with multiple devices (e.g., 1, 2, 3, 4, 5, 10,20, 50 . . . ) for purposes of controlling the energy delivery throughsuch devices.

In some embodiments, the device is designed to physically surround aparticular tissue region for purposes of energy delivery (e.g., thedevice may be flexibly shaped around a particular tissue region). Forexample, in some embodiments, the device may be flexibly shaped around ablood vessel (e.g., pulmonary vein) for purposes of delivering energy toa precise region within the tissue.

In some embodiments, the energy delivery device is provided as two ormore separate antenna attached to the same or different power supplies.In some embodiments, the different antenna are attached to the samehandle, while in other embodiments different handles are provided foreach antenna. In some embodiments, multiple antennae are used within apatient simultaneously or in series (e.g., switching) to deliver energyof a desired intensity and geometry within the patient. In someembodiments, the antennas are individually controllable. In someembodiments, the multiple antennas may be operated by a single user, bya computer, or by multiple users.

In some embodiments, the energy delivery devices are designed to operatewithin a sterile field. The present invention is not limited to aparticular sterile field setting. In some embodiments, the sterile fieldincludes a region surrounding a subject (e.g., an operating table). Insome embodiments, the sterile field includes any region permittingaccess only to sterilized items (e.g., sterilized devices, sterilizedaccessory agents, sterilized body parts). In some embodiments, thesterile field includes any region vulnerable to pathogen infection. Insome embodiments, the sterile field has therein a sterile field barrierestablishing a barrier between a sterile field and a non-sterile field.The present invention is not limited to a particular sterile fieldbarrier. In some embodiments, the sterile field barrier is the drapessurrounding a subject undergoing a procedure involving the systems ofthe present invention (e.g., tissue ablation). In some embodiments, aroom is sterile and provides the sterile field. In some embodiments, thesterile field barrier is established by a user of the systems of thepresent invention (e.g., a physician). In some embodiments, the sterilefield barrier hinders entry of non-sterile items into the sterile field.In some embodiments, the energy delivery device is provided in thesterile field, while one or more other components of the system (e.g.,the power supply) are not contained in the sterile field.

In some embodiments, the energy delivery devices have therein protectionsensors designed to prevent undesired use of the energy deliverydevices. The energy delivery devices are not limited to a particulartype or kind of protection sensors. In some embodiments, the energydelivery devices have therein a temperature sensor designed to measurethe temperature of, for example, the energy delivery device and/or thetissue contacting the energy delivery device. In some embodiments, as atemperature reaches a certain level the sensor communicates a warning toa user via, for example, the processor. In some embodiments, the energydelivery devices have therein a skin contact sensor designed detectcontact of the energy delivery device with skin (e.g., an exteriorsurface of the skin). In some embodiments, upon contact with undesiredskin, the skin contact sensor communicates a warning to a user via, forexample, the processor. In some embodiments, the energy delivery deviceshave therein an air contact sensor designed detect contact of the energydelivery device with ambient air (e.g., detection through measurement ofreflective power of electricity passing through the device). In someembodiments, upon contact with undesired air, the skin contact sensorcommunicates a warning to a user via, for example, the processor. Insome embodiments, the sensors are designed to prevent use of the energydelivery device (e.g., by automatically reducing or preventing powerdelivery) upon detection of an undesired occurrence (e.g., contact withskin, contact with air, undesired temperature increase/decrease). Insome embodiments, the sensors communicate with the processor such thatthe processor displays a notification (e.g., a green light) in theabsence of an undesired occurrence. In some embodiments, the sensorscommunicate with the processor such that the processor displays anotification (e.g., a red light) in the presence of an undesiredoccurrence and identifies the undesired occurrence.

In some embodiments, the energy delivery devices are used above amanufacturer's recommended power rating. In some embodiments, coolingtechniques described herein are applied to permit higher power delivery.The present invention is not limited to a particular amount of powerincrease. In some embodiments, power ratings exceed manufacturer'srecommendation by 5× or more (e.g., 5×, 6×, 10×, 15×, 20×, etc.).

In addition, the devices of the present invention are configured todeliver energy from different regions of the device (e.g., outerconductor segment gaps, described in more detail below) at differenttimes (e.g., controlled by a user) and at different energy intensities(e.g., controlled by a user). Such control over the device permits thephasing of energy delivery fields for purposes of achieving constructivephase interference at a particular tissue region or destructive phaseinterference at a particular tissue region. For example, a user mayemploy energy delivery through two (or more) closely positioned outerconductor segments so as to achieve a combined energy intensity (e.g.,constructive phase interference). Such a combined energy intensity maybe useful in particularly deep or dense tissue regions. In addition,such a combined energy intensity may be achieved through utilization oftwo (or more) devices. In some embodiments, phase interference (e.g.,constructive phase interference, destructive phase interference),between one or more devices, is controlled by a processor, a tuningelement, a user, and/or a power splitter. Thus, the user is able tocontrol the release of energy through different regions of the deviceand control the amount of energy delivered through each region of thedevice for purposes of precisely sculpting an ablation zone.

In some embodiments, the energy delivery systems of the presentinvention utilize energy delivery devices with optimized characteristicimpedance, energy delivery devices having cooling passage channels,energy delivery devices with a center fed dipole, and energy deliverydevices having a linear array of antennae components (each described inmore detail above and below).

As described in the Summary of the Invention, above, the presentinvention provides a wide variety of methods for cooling the devices.Some embodiments employ meltable barriers that, upon melting, permit thecontact of chemicals that carry out an endothermic reaction. An exampleof such an embodiment is shown in FIG. 3. FIGS. 3A and 3B display aregion of a coaxial transmission line (e.g., a channel) havingpartitioned segments with first and second materials blocked by meltablewalls for purposes of preventing undesired device heating (e.g., heatingalong the outer conductor). FIGS. 3A and 3B depict a standard coaxialtransmission line 300 configured for use within any of the energydelivery devices of the present invention. As shown in FIG. 3A, thecoaxial transmission line 300 has a center conductor 310, a dielectricmaterial 320, and an outer conductor 330. In addition, the coaxialtransmission line 300 has therein four partitioned segments 340segregated by walls 350 (e.g., meltable wax walls). The partitionedsegments 340 are divided into first partitioned segments 360 and secondpartitioned segments 370. In some embodiments, as shown in FIG. 3A, thefirst partitioned segments 360 and second partitioned segments 370 aresuccessively staggered. As shown in FIG. 3A, the first partitionedsegments 360 contain a first material (shading type one) and the secondpartitioned segments 370 contain a second material (shading type two).The walls 350 prevent the first material and second material frommixing. FIG. 3B shows the coaxial transmission line 300 described inFIG. 3A following an event (e.g., a temperature increase at one of thepartitioned segments 340). As shown, one of the walls 350 has meltedthereby permitting mixing of the first material contained in a region360 and second material contained in a region 370. FIG. 3B further showsnon-melted walls 350 where the temperature increase did not rise above acertain temperature threshold.

FIG. 4 shows an alternative embodiment. FIGS. 4A and 4B display acoaxial transmission line embodiment having partitioned segmentssegregated by meltable walls containing first and second materials(e.g., materials configured to generate a temperature reducing chemicalreaction upon mixing) preventing undesired device heating (e.g., heatingalong the outer conductor). FIGS. 4A and 4B show a coaxial transmissionline 400 configured for use within any of the energy delivery devices ofthe present invention. As shown in FIG. 4A, the coaxial transmissionline 400 has a center conductor 410, a dielectric material 420, and anouter conductor 430. In addition, the coaxial transmission line 400 hastherein four partitioned segments 440 segregated by walls 450. The walls450 each contain a first material 460 separated from a second material470. FIG. 4B shows the coaxial transmission line 400 described in FIG.4A following an event (e.g., a temperature increase at one of thepartitioned segments 440). As shown, one of the walls 450 has meltedthereby permitting mixing of the first material 460 and second material470 within the adjacent partitioned segments 440. FIG. 4B furtherdemonstrates non-melted walls 450 where the temperature increase did notrise above a certain temperature threshold.

In some embodiments, the device further comprises an anchoring elementfor securing the antenna at a particular tissue region. The device isnot limited to a particular type of anchoring element. In someembodiments, the anchoring element is an inflatable balloon (e.g.,wherein inflation of the balloon secures the antenna at a particulartissue region). An additional advantage of utilizing an inflatableballoon as an anchoring element is the inhibition of blood flow or airflow to a particular region upon inflation of the balloon. Such air orblood flow inhibition is particularly useful in, for example, cardiacablation procedures and ablation procedures involving lung tissue,vascular tissue, and gastrointestinal tissue. In some embodiments, theanchoring element is an extension of the antenna designed to engage(e.g., latch onto) a particular tissue region. Further examples include,but are not limited to, the anchoring elements described in U.S. Pat.Nos. 6,364,876, and 5,741,249; each herein incorporated by reference intheir entireties.

Thus, in some embodiments, the devices of the present invention are usedin the ablation of a tissue region having high amounts of air and/orblood flow (e.g., lung tissue, cardiac tissue, gastrointestinal tissue,vascular tissue). In some embodiments involving ablation of tissueregions having high amounts of air and/or blood flow, an element isfurther utilized for inhibiting the air and/or blood flow to that tissueregion. The present invention is not limited to a particular air and/orblood flow inhibition element. In some embodiments, the device iscombined with an endotracheal/endobronchial tube. In some embodiments, aballoon attached with the device may be inflated at the tissue regionfor purposes of securing the device(s) within the desired tissue region,and inhibiting blood and/or air flow to the desired tissue region.

Thus, in some embodiments, the systems, devices, and methods of thepresent invention provide an ablation device coupled with a componentthat provides occlusion of a passageway (e.g., bronchial occlusion). Theocclusion component (e.g., inflatable balloon) may be directly mountedon the ablation system or may be used in combination with anothercomponent (e.g., an endotracheal or endobronchial tube) associated withthe system.

In some embodiments, the devices of the present invention may be mountedonto additional medical procedure devices. For example, the devices maybe mounted onto endoscopes, intravascular catheters, or laproscopes. Insome embodiments, the devices are mounted onto steerable catheters. Insome embodiments, a flexible catheter is mounted on an endoscope,intravascular catheter or laparoscope. For example, the flexiblecatheter, in some embodiments, has multiple joints (e.g., like acentipede) that permits bending and steering as desired to navigate tothe desired location for treatment.

Energy Delivery Devices with Optimized Characteristic Impedance

In some embodiments, the energy delivery systems of the presentinvention utilize devices configured for delivery of microwave energywith an optimized characteristic impedance (see, e.g., U.S. patentapplication Ser. No. 11/728,428; herein incorporated by reference in itsentirety). Such devices are configured to operate with a characteristicimpedance higher than 50Ω (e.g., between 50 and 90Ω; e.g., higher than50, . . . , 55, 56, 57, 58, 59, 60, 61, 62, . . . 90Ω, preferably at77Ω).

Energy delivery devices configured to operate with optimizedcharacteristic impedance are particularly useful in terms of tissueablation procedures, and provide numerous advantages over non-optimizeddevices. For example, a major drawback with currently available medicaldevices that utilize microwave energy is the undesired dissipation ofthe energy through transmission lines onto a subject's tissue resultingin undesired burning. Such microwave energy loss results fromlimitations within the design of currently available medical devices.Standard impedance for coaxial transmission lines within medical devicesis 50Ω or lower. Generally, coaxial transmission lines with impedancelower than 50Ω have high amounts of heat loss due to the presence ofdielectric materials with finite conductivity values. As such, medicaldevices with coaxial transmission lines with impedance at 50Ω or lowerhave high amounts of heat loss along the transmission lines. Inparticular, medical devices utilizing microwave energy transmit energythrough coaxial cables having therein a dielectric material (e.g.,polyfluorothetraethylene or PTFE) surrounding an inner conductor.Dielectric materials such as PTFE have a finite conductivity, whichresult in the undesired heating of transmission lines. This isparticularly true when one supplies the necessary amounts of energy fora sufficient period of time to enable tissue ablation. Energy deliverydevices configured to operate with optimized characteristic impedanceovercome this limitation by lacking, or substantially lacking, a soliddielectric insulator. For example, using air in place of a traditionaldielectric insulator results in an efficient device operating at 77Ω. Insome embodiments, the devices employ a near-zero conductivity dielectricmaterial (e.g., air, water, inert gases, vacuum, partial vacuum, orcombinations thereof). The overall temperature of the transmission lineswithin such devices are greatly reduced through use of coaxialtransmission lines with near-zero conductivity dielectric materials, andtherefore, greatly reduce undesired tissue heating.

In addition, by providing a coaxial transmission line with a dielectricmaterial having near-zero conductivity, and avoiding the use of typicaldielectric polymers, the coaxial transmission line may be designed suchthat it can fit within small needles (e.g., 18-20 gauge needles).Typically, medical devices configured to delivery microwave energy aredesigned to fit within large needles due to bulky dielectric materials.Microwave ablation has not been extensively applied clinically due tothe large probe size (14 gauge) and relatively small zone of necrosis(1.6 cm in diameter) (Seki T et al., Cancer 74:817 (1994)) that iscreated by the only commercial device (Microtaze, Nippon Shoji, Osaka,Japan. 2.450 MHz, 1.6 mm diameter probe, 70 W for 60 seconds). Otherdevices use a cooling external water jacket that also increases probesize and can increase tissue damage. These large probe sizes increasethe risk of complications when used in the chest and abdomen.

Energy Delivery Devices Having Coolant Passage Channels

In some embodiments, the energy delivery systems of the presentinvention utilize energy delivery devices having coolant passagechannels (see, e.g., U.S. Pat. No. 6,461,351, and U.S. patentapplication Ser. No. 11/728,460; herein incorporated by reference in itsentirety). In particular, the energy delivery systems of the presentinvention utilize devices with coaxial transmission lines that allowcooling by flowing a cooling material through the dielectric and/or theinner or outer conductor of the coaxial component. In some embodiments,the devices are configured to minimize the diameter of the device, whilepermitting the passage of the coolant. This is accomplished, in someembodiments, by replacing strips of the inner or outer conductor and/orsolid dielectric material with channels through which a coolant istransferred. In some embodiments, the channels are generated bystripping the outer or inner conductor and/or solid dielectric materialalong the length of the coaxial cable from one or more (e.g., two,three, four) zones. With the removed portions of the outer or innerconductor and/or solid dielectric material creating channels fortransfer of the coolant, the stripped component fits within a smallerouter conductor than it did prior to removal of the outer or innerconductor and/or solid dielectric material. This provides for smallerdevices with all of the advantages derived therefrom. In someembodiments where multiple channels are employed, coolant transfer maybe in alternative directions through one or more of the channels. Anadvantage of such devices is that the diameter of the coaxial cable doesnot need to be increased to accommodate coolant. This permits the use ofcooled devices that are minimally invasive and permit access to regionsof a body that are otherwise inaccessible or accessible only withundesired risk. The use of coolant also permits greater energy deliveryand/or energy deliver for prolonged periods of time. Additional coolingembodiments are described above in the Summary of the Invention.

In some embodiments, the device has a handle attached with the device,wherein the handle is configured to, for example, control the passing ofcoolant into and out of the coolant channels. In some embodiments, thehandle automatically passes coolant into and out of the coolant channelsafter a certain amount of time and/or as the device reaches a certainthreshold temperature. In some embodiments, the handle automaticallystops passage of coolant into and out of the coolant channels after acertain amount of time and/or as the temperature of the device dropsbelow a certain threshold temperature. In some embodiments, the handleis manually controlled to adjust coolant flow.

FIG. 5 shows a schematic drawing of a handle configured to control thepassing of coolant into and out of the coolant channels. As shown inFIG. 5, the handle 500 is engaged with a coaxial transmission line 510having a coolant channel 520. The handle 500 has therein a coolant inputchannel 530, a coolant output channel 540, a first blocking component550 (e.g., a screw or pin) configured to prevent flow through channel520 behind the blocking component and a second blocking component 560.The coolant input channel 530 is configured to provide coolant to thecoolant channel 520. The coolant output channel 540 is configured toremove coolant from the coolant channel 520 (e.g., coolant that hascirculated and removed heat from a device). The coolant input channel530 and coolant output channel 540 are not limited to particular sizesor means for providing and removing coolant. The first blockingcomponents 550 and second blocking component 560 are not limited toparticular sizes or shapes. In some embodiments, the first blockingcomponent 550 and second blocking component 560 each have a circularshape and a size that matches the diameter of the coolant input channel530 and the coolant output channel 540. In some embodiments, the firstblocking component 550 and second blocking component 560 are used toblock the backflow of coolant to a certain region of the handle 500. Insome embodiments, the blocking components are configured such that onlya portion (e.g., 1%, 5%, 10%, 20%, 50%, 75%, 85%, 95%, 99%) of thechannel is blocked. Blocking only a portion permits the user, forexample, to vary the pressure gradients within the coolant channel 520.

Energy delivery devices having coolant passage channels allow foradjustment of the characteristic impedance of the coaxial transmissionline. In particular, the dielectric properties of the coolant (or of anon-coolant material that is passed through the channel(s)) may beadjusted to alter the bulk complex permittivity of the dielectric mediumseparating the outer and inner conductors. As such, changes in thecharacteristic impedance are made during a procedure to, for example,optimize energy delivery, tissue effects, temperature, or other desiredproperties of the system, device, or application. In other embodiments,a flow material is selected prior to a procedure based on the desiredparameters and maintained throughout the entire procedure. Thus, suchdevices provide an antenna radiating in a changing dielectricenvironment to be adjusted to resonate in the changing environment to,for example, allow adaptive tuning of the antenna to ensure peakefficiency of operation. As desired, the fluid flow also allows heattransfer to and from the coaxial cable. In some embodiments, thechannels or hollowed out areas contain a vacuum or partial vacuum. Insome embodiments, impedance is varied by filling the vacuum with amaterial (e.g., any material that provides the desired result).Adjustments may be made at one or more time points or continuously.

The energy delivery devices having coolant passage channels are notlimited to particular aspects of the channels. In some embodiments, thechannel is cut through only a portion of the outer or inner conductorand/or solid dielectric material so that the flowed material is incontact with either the inner or outer conductor and the remainingdielectric material. In some embodiments, the channels are linear alongthe length of the coaxial cable. In some embodiments, the channels arenon-linear. In some embodiments, where more than one channel is used,the channels run parallel to one another. In other embodiments, thechannels are not parallel. In some embodiments, the channels cross oneanother. In some embodiments, the channels remove over 50% (e.g., 60%,70%, 80%, etc.) of the outer or inner conductor and/or solid dielectricmaterial. In some embodiments, the channels remove substantially all ofthe outer or inner conductor and/or solid dielectric material.

The energy delivery devices having coolant passage channels are notlimited by the nature of the material that is flowed through the outeror inner conductor and/or solid dielectric material. In someembodiments, the material is selected to maximize the ability to controlthe characteristic impedance of the device, to maximize heat transfer toor from the coaxial cable, or to optimize a combination of control ofthe characteristic impedance and heat transfer. In some embodiments, thematerial that is flowed through the outer or inner conductor and/orsolid dielectric material is a liquid. In some embodiments, the materialis a gas. In some embodiments, the material is a combination of liquidor gas. The present invention is not limited to the use of liquids orgasses. In some embodiments, the material is a slurry, a gel, or thelike. In some embodiments, a coolant fluid is used. Any coolant fluidnow known or later developed may be used. Exemplary coolant fluidsinclude, but are not limited to, one or more of or combinations of,water, glycol, air, inert gasses, carbon dioxide, nitrogen, helium,sulfur hexafluoride, ionic solutions (e.g., sodium chloride with orwithout potassium and other ions), dextrose in water, Ringer's lactate,organic chemical solutions (e.g., ethylene glycol, diethylene glycol, orpropylene glycol), oils (e.g., mineral oils, silicone oils, fluorocarbonoils), liquid metals, freons, halomethanes, liquified propane, otherhaloalkanes, anhydrous ammonia, sulfur dioxide. In some embodiments, thecoolant fluids are pre-cooled prior to delivery into the energy deliverdevice. In some embodiments, the coolant fluids are cooled with acooling unit following entry into the energy delivery device. In someembodiments, the material passed through the dielectric material isdesigned to generate an endothermic reaction upon contact with anadditional material.

The energy delivery devices having coolant passage channels areconfigured to permit control over the parameters of fluid infusionthrough the device. In some embodiments, the device is manually adjustedby the user (e.g., a treating physician or technician) as desired. Insome embodiments, the adjustments are automated. In some embodiments,the devices are configured with or used with sensors that provideinformation to the user or the automated systems (e.g., comprisingprocessors and/or software configured for receiving the information andadjusting fluid infusion or other device parameters accordingly).Parameters that may be regulated include, but are not limited to, speedof infusion of the fluid, concentration of ions or other components thataffect the properties of the fluid (e.g., dielectric properties, heattransfer properties, flow rate, etc.), temperature of the fluid, type offluid, mixture ratios (e.g., mixtures of gas/fluid for precise tuning orcooling). Thus, energy delivery devices having coolant passage channelsare configured to employ a feed-back loop that can change one or moredesired parameters to tune the device (e.g., antenna) more accurately,or speed up the infusion of the fluid if the device, portions of thedevice, or tissue of the subject reaches an undesired temperature (or atemperature for an undesired period of time).

The energy delivery devices having coolant passage channels providenumerous advantages over the currently available systems and devices.For example, by providing a coaxial transmission line with channelscarved out of, and that can substantially remove the volume of soliddielectric material, the coaxial transmission line may be designed suchthat it can fit within very small needles (e.g., 18-20 gauge needles orsmaller). Typically, medical devices configured to delivery microwaveenergy are designed to fit within large needles due to bulky dielectricmaterials. Other devices use a cooling external water jacket that alsoincreases probe size and can increase tissue damage. These large probesizes increase the risk of complications when used in the chest andabdomen. In some embodiments of the present invention, the maximum outerdiameter of the portion of the device that enters a subject is 16-18gauge or less (20 gauge or less).

FIG. 6 shows a transverse cross-section schematic of standard coaxialcable embodiments and embodiments of the present invention havingcoolant passages. As shown in FIG. 6, a conventional coaxial cable 600and two exemplary coaxial cables of the present invention, 610 and 620are provided. A coaxial cable is made, generally, of three separatespaces: a metallic inner conductor 630, a metallic outer conductor 650,and a space between them. The space between them is usually filled witha low-loss dielectric material 640 (e.g., polyfluorotetraethylene, orPTFE) to mechanically support the inner conductor and maintain it withthe outer conductor. The characteristic impedance of a coaxial cable isfixed by the ratio of diameters of the inner conductor and dielectricmaterial (i.e., inner diameter of the outer conductor) and thepermittivity of the space between them. Usually, the permittivity isfixed because of the solid polymer comprising it. However, inembodiments of the present invention, a fluid with variable permittivity(or conductivity) at least partially occupies this space, permitting thecharacteristic impedance of the cable to be adjusted.

Still referring to FIG. 6, in one embodiment of the present invention,the coaxial cable 610 has the outer portion of the dielectric materialremoved to create a channel between the dielectric material 640 and theouter conductor 650. In the embodiments shown, the created space isseparated into four distinct channels 670 by the addition of supportlines 660 configured to maintain the space between the outer conductor650 and the solid dielectric material 640. The support lines 660 may bemade of any desired material and may be the same or a different materialas the solid dielectric material 640. In some embodiments, so as toavoid undesired heating of the device (e.g., undesired heating of theouter conductor), the support lines 660 are made of a biocompatible andmeltable material (e.g., wax). The presence of multiple channels permitsone or more of the channels to permit flow in one direction (towards theproximal end of the cable) and one or more other channels to permit flowin the opposite direction (towards the distal end of the cable).

Still referring to FIG. 6, in another embodiment, the coaxial cable 620has a substantial portion of the solid dielectric material 640 removed.Such an embodiment may be generated, for example, by stripping away thesolid dielectric material 640 down to the surface of inner conductor 630on each of four sides. In another embodiment, strips of dielectricmaterial 640 are applied to an inner conductor 630 to create thestructure. In this embodiment, four channels 670 are created. Byremoving a substantial amount of the dielectric material 640, thediameter of the outer conductor 650 is substantially reduced. Thecorners provided by the remaining dielectric material 640 provide thesupport to maintain the position of the outer conductor 650 with respectto the inner conductor 630. In this embodiment, the overall diameter ofthe coaxial cable 620 and the device is substantially reduced.

In some embodiments, the devices have a coolant passage formed throughinsertion of a tube configured to circulate coolant through thedielectric portion or inner or outer conductors of any of the energyemission devices of the present invention. FIG. 7 shows a coolantcirculating tube 700 (e.g., coolant needle, catheter) positioned withinan energy emission device 710 having an outer conductor 720, adielectric material 730, and an inner conductor 740. As shown in FIG. 7,the tube 700 is positioned along the outside edge of the dielectricmaterial 730 and inside edge of the outer conductor 720, with the innerconductor 740 positioned approximately in the center of the dielectricmaterial 730. In some embodiments, the tube 700 is positioned within thedielectric material 730 such that it does not contact the outerconductor 720. In some embodiments, the tube 700 has multiple channels(not shown) for purposes of recirculating the coolant within the tube700 without passing the coolant into the dielectric material 730 and/orthe outer conductor 720, thereby cooling the dielectric material 730and/or the outer conductor 720 with the exterior of the tube 700.

Energy Delivery Device with a Center Fed Dipole

In some embodiments, the energy delivery systems of the presentinvention utilize energy delivery devices employing a center fed dipolecomponent (see, e.g., U.S. patent application Ser. No. 11/728,457;herein incorporated by reference in its entirety). The devices are notlimited to particular configurations. In some embodiments, the deviceshave therein a center fed dipole for heating a tissue region throughapplication of energy (e.g., microwave energy). In some embodiments,such devices have a coaxial cable connected to a hollow tube (e.g.,where the interior diameter is at least 50% of the exterior diameter;e.g., where the interior diameter is substantially similar to theexterior diameter). The coaxial cable may be a standard coaxial cable,or it may be a coaxial cable having therein a dielectric component witha near-zero conductivity (e.g., air). The hollow tube is not limited toa particular design configuration. In some embodiments, the hollow tubeassumes the shape of (e.g., diameter of), for example, a 20-gaugeneedle. Preferably, the hollow tube is made of a solid, rigid conductivematerial (e.g., any number of metals, conductor-coated ceramics orpolymers, etc.). In some embodiments, the hollow tube is configured witha sharpened point or the addition of a stylet on its distal end topermit direct insertion of the device into a tissue region without theuse of, for example, a cannula. The hollow tube is not limited to aparticular composition (e.g., metal, plastic, ceramic). In someembodiments, the hollow tube comprises, for example, copper or copperalloys with other hardening metals, silver or silver alloys with otherhardening metals, gold-plated copper, metal-plated Macor (machinableceramic), metal-plated hardened polymers, and/or combinations thereof.

In some embodiments, the center fed dipole is configured to adjust theenergy delivery characteristics in response to heating so as to providea more optimal energy delivery throughout the time period of a process.In some embodiments, this is achieved by using a material that changesvolume in response to temperature changes such that the change in thevolume of the material changes to the energy delivery characteristics ofthe device. In some embodiments, for example, an expandable material isplaced in the device such that the resonant portion of the center feddipole component or the stylet is pushed distally along the device inresponse to heating. This changes the tuning of the device to maintain amore optimal energy delivery. The maximum amount of movement can beconstrained, if desired, by, for example, providing a locking mechanismthat prevents extension beyond a particular point.

The energy delivery devices employing a center fed dipole component arenot limited by the manner in which the hollow tube is connected to thecoaxial cable. In some embodiments, a portion of the outer conductor atthe distal end of the coaxial cable feedline is removed, exposing aregion of solid dielectric material. The hollow tube can be positionedonto the exposed dielectric material and attached by any means. In somesome embodiments, a physical gap between the outer conductor and thehollow tube is provided. In some some embodiments, the hollow tube iscapacitively or conductively attached to the feedline at its centerpoint such that the electrical length of the hollow tube comprises afrequency-resonant structure when inserted into tissue.

In use, the energy delivery devices employing a center fed dipolecomponent are configured such that an electric field maximum isgenerated at the open distal end of the hollow tube. In someembodiments, the distal end of the hollow tube has a pointed shape so asto assist in inserting the device though a subject and into a tissueregion. In some embodiments, the entire device is hard and rigid so asto facilitate linear and direct insertion directly to a target site. Insome embodiments, the structure resonates at, for example, ˜2.45 GHz, ascharacterized by a minimum in the reflection coefficient (measured atthe proximal end of the feedline) at this frequency. By changing thedimensions of the device (e.g., length, feed point, diameter, gap, etc.)and materials (dielectric materials, conductors, etc.) of the antenna,the resonant frequency may be changed. A low reflection coefficient at adesired frequency ensures efficient transmission of energy from theantenna to the medium surrounding it.

Preferably, the hollow tube is of length λ/2, where λ is theelectromagnetic field wavelength in the medium of interest (e.g., ˜18 cmfor 2.45 GHz in liver) to resonate within the medium. In someembodiments, the length of the hollow tube is approximately λ/2, where λis the electromagnetic field wavelength in the medium of interest toresonate within the medium, such that a minimum of power reflection atthe proximal end is measured. However, deviations from this length maybe employed to generate resonant wavelengths (e.g., as the surroundingmaterials are changed). Preferably, the inner conductor of a coaxialcable is extended with its distal end at the tube center (e.g., at λ/4from the end of the tube) and configured such that the inner conductormaintains electrical contact at the tube center, although deviationsfrom this position are permitted (e.g., to generate resonantwavelengths).

The hollow tube portion of the present invention may have a wide varietyof shapes. In some embodiments, the tube is cylindrical throughout itslength. In some embodiments, tube tapers from a center position suchthat it has a smaller diameter at its end as compared to its center.Having a smaller point at the distal end assists in penetrating asubject to arrive at the target region. In some embodiments, where theshape of the hollow tube deviates from a cylindrical shape, the tubemaintains a symmetrical structure on either side of its longitudinalcenter. However, the devices are not limited by the shape of the hollowtube, so long as the functional properties are achieved (i.e., theability to deliver desired energy to a target region).

In some embodiments, the center-fed dipole components may be added tothe distal end of a wide variety of ablation devices to provide thebenefits described herein. Likewise, a wide variety of devices may bemodified to accept the center-fed dipole components of the presentinvention.

In some embodiments, the devices have a small outer diameter. In someembodiments, the center-fed dipole component of the invention isdirectly used to insert the invasive component of the device into asubject. In some such embodiments, the device does not contain acannula, allowing for the invasive components to have a smaller outerdiameter. For example, the invasive component can be designed such thatit fits within or is the size of very small needles (e.g., 18-20 gaugeneedles or smaller).

FIG. 8 schematically shows the distal end of a device 800 (e.g., antennaof an ablation device) of the present invention that comprises a centerfed dipole component 810 of the present invention. One skilled in theart will appreciate any number of alternative configurations thataccomplish the physical and/or functional aspects of the presentinvention. As shown, the center fed dipole device 800 has therein ahollow tube 815, a coaxial transmission line 820 (e.g., a coaxialcable), and a stylet 890. The center fed dipole device 800 is notlimited to a particular size. In some embodiments, the size of thecenter fed dipole device 800 is small enough to be positioned at atissue region (e.g., a liver) for purposes of delivering energy (e.g.,microwave energy) to that tissue region.

Referring again to FIG. 8, the hollow tube 815 is not limited to aparticular material (e.g., plastic, ceramic, metal, etc.). The hollowtube 815 is not limited to a particular length. In some embodiments, thelength of the hollow tube is λ/2, where λ is the electromagnetic fieldwavelength in the medium of interest (e.g., ˜18 cm for 2.45 GHz inliver). The hollow tube 815 engages the coaxial transmission line 820such that the hollow tube 815 is attached to the coaxial transmissionline 820 (described in more detail below). The hollow tube 815 hastherein a hollow tube matter 860. The hollow tube 815 is not limited toa particular type of hollow tube matter. In some embodiments, the hollowtube matter 860 is air, fluid or a gas.

Still referring to FIG. 8, the hollow tube 815 is not limited to aparticular shape (e.g., cylindrical, triangular, squared, rectangular,etc.). In some embodiments, the shape of the hollow tube 815 is of aneedle (e.g., a 20-gauge needle, an 18-gauge needle). In someembodiments, the hollow tube 815 is divided into two portions each ofvariable length. As shown, the hollow tube 815 is divided into twoportions each of equal length (e.g., each portion having a length ofλ/4). In such embodiments, the shapes of each portion are symmetrical.In some embodiments, the hollow tube has a diameter equal to or lessthan a 20-gauge needle, a 17-gauge needle, a 12-gauge needle, etc.

Still referring to FIG. 8, the distal end of the hollow tube 815 engagesa stylet 890. The device 800 is not limited to a particular stylet 890.In some embodiments, the stylet 890 is designed to facilitatepercutaneous insertion of the device 800. In some embodiments, thesytlet 890 engages the hollow tube 815 by sliding inside the hollow tube815 such that the stylet 890 is secured.

Still referring to FIG. 8, the coaxial transmission line 820 is notlimited to a particular type of material. In some embodiments, theproximal coaxial transmission line 820 is constructed fromcommercial-standard 0.047-inch semi-rigid coaxial cable. In someembodiments, the coaxial transmission line 820 is metal-plated (e.g.,silver-plated, copper-plated), although the present invention is not solimited. The proximal coaxial transmission line 820 is not limited to aparticular length.

Still referring to FIG. 8, in some embodiments, the coaxial transmissionline 820 has a coaxial center conductor 830, a coaxial dielectricmaterial 840, and a coaxial outer conductor 850. In some embodiments,the coaxial center conductor 830 is configured to conduct cooling fluidalong its length. In some embodiments, the coaxial center conductor 830is hollow. In some embodiments, the coaxial center conductor 830 has adiameter of, for example, 0.012 inches. In some embodiments, the coaxialdielectric material 840 is polyfluorotetraethylene (PTFE). In someembodiments, the coaxial dielectric material 840 has a near-zeroconductivity (e.g., air, fluid, gas).

Still referring to FIG. 8, the distal end of the coaxial transmissionline 820 is configured to engage the proximal end of the hollow tube815. In some embodiments, the coaxial center conductor 830 and thecoaxial dielectric material 840 extend into the center of the hollowtube 815. In some embodiments, the coaxial center conductor 820 extendsfurther into the hollow tube 815 than the coaxial dielectric material840. The coaxial center conductor 820 is not limited to a particularamount of extension into the hollow tube 815. In some embodiments, thecoaxial center conductor 820 extends a length of λ/4 into the hollowtube 815. The distal end of the coaxial transmission line 820 is notlimited to a particular manner of engaging the proximal end of thehollow tube 815. In some embodiments, the proximal end of the hollowtube engages the coaxial dielectric material 840 so as to secure thehollow tube 815 with the coaxial transmission line 820. In someembodiments, where the coaxial dielectric material 840 has a near-zeroconductivity, the hollow tube 815 is not secured with the coaxialtransmission line 820. In some embodiments, the distal end of thecoaxial center conductor 830 engages the walls of the hollow tube 815directly or though contact with a conductive material 870, which may bemade of the same material as the coaxial center conductor or may be of adifferent material (e.g., a different conductive material).

Still referring to FIG. 8, in some embodiments, a gap 880 exists betweenthe distal end of the coaxial transmission line outer conductor 850 andthe hollow tube 815 thereby exposing the coaxial dielectric material840. The gap 880 is not limited to a particular size or length. In someembodiments, the gap 880 ensures an electric field maximum at theproximal end of the coaxial transmission line 880 and the distal openend of the hollow tube 815. In some embodiments, the center fed dipoledevice 810 resonates at ˜2.45 GHz, as characterized by a minimum in thereflection coefficient at this frequency. By changing the dimensions(length, feed point, diameter, gap, etc.) and materials (dielectricmaterials, conductors, etc.) of the device the resonant frequency may bechanged. A low reflection coefficient at this frequency ensuresefficient transmission of energy from the antenna to the mediumsurrounding it.

Still referring to FIG. 8, in some embodiments, the gap 880 is filledwith a material (e.g., epoxy) so bridge the coaxial transmission line820 and the hollow tube 815. The devices are not limited to a particulartype or kind of substantive material. In some embodiments, thesubstantive material does not interfere with the generation or emissionof an energy field through the device. In some embodiments, the materialis biocompatible and heat resistant. In some embodiments, the materiallacks or substantially lacks conductivity. In some embodiments, thematerial further bridges the coaxial transmission line 820 and thehollow tube 815 with the coaxial center conductor 830. In someembodiments, the substantive material is a curable resin. In someembodiments, the material is a dental enamel (e.g., XRV Herculiteenamel; see, also, U.S. Pat. Nos. 6,924,325, 6,890,968, 6,837,712,6,709,271, 6,593,395, and 6,395,803, each herein incorporated byreference in their entireties). In some embodiments, the substantivematerial is cured (e.g., cured with a curing light such as, for example,L. E. Demetron II curing light) (see, e.g., U.S. Pat. Nos. 6,994,546,6,702,576, 6,602,074 and 6,435,872). Thus, the present inventionprovides ablation devices comprising a cured enamel resin. Such a resinis biocompatible and rigid and strong.

Energy Delivery Devices Having a Linear Array of Antenna Components

In some embodiments, the energy delivery systems of the presentinvention utilize energy delivery devices having a linear array ofantennae components (see, e.g., U.S. Provisional Patent Application No.60/831,055; herein incorporated by reference in its entirety). Thedevices are not limited to particular configurations. In someembodiments, the energy delivery devices having a linear array ofantennae components have therein an antenna comprising an innerconductor and an outer conductor, wherein the outer conductor isprovided in two or more linear segments separated by gaps, such that thelength and position of the segments is configured for optimized deliveryof energy at the distal end of the antenna. For example, in someembodiments, an antenna comprises a first segment of outer conductorthat spans the proximal end of the antenna to a region near the distalend and a second segment of outer conductor distal to the first segmentwherein a gap separates or partially separates the first and secondsegments. The gaps may entirely circumscribe the outer conductor or mayonly partially circumscribe the outer conductor. In some embodiments,the length of the second segment is λ/2, λ/4, etc., although the presentinvention is not so limited. In some embodiments one or more additional(e.g., third, fourth, fifth) segments are provided distal to the secondsegment, each of which is separated from the other by a gap. In someembodiments, the antenna is terminated with a conductive terminal endthat is in electronic communication with the inner conductor. In someembodiments, the conductive terminal end comprises a disc having adiameter substantially identical to the diameter of the outer conductor.Such antennae provide multiple peaks of energy delivery along the lengthof the distal end of the antenna, providing a broader region of energydelivery to target larger regions of tissue. The location and positionof the peaks is controlled by selecting the length of the outerconductor segments and by controlling the amount of energy delivered.

The energy delivery devices having a linear array of antennae componentsare not limited by the nature of the various components of the antenna.A wide variety of components may be used to provide optimal performance,including, but not limited to, the use of a variety of materials for theinner and outer conductors, the use of a variety of materials andconfigurations for dielectric material between the inner and outerconductors, the use of coolants provided by a variety of differentmethods.

In certain embodiments, the devices comprise a linear antenna, whereinthe linear antenna comprises an outer conductor enveloped around aninner conductor, wherein the inner conductor is designed to receive andtransmit energy (e.g., microwave energy), wherein the outer conductorhas therein a series of gap regions (e.g., at least two) positionedalong the outer conductor, wherein the inner conductor is exposed at thegap regions, wherein the energy transmitting along the inner conductoris emitted through the gap regions. The devices are not limited to aparticular number of gap regions (e.g., 2, 3, 4, 5, 6, 10, 20, 50). Insome embodiments, the positioning of the gaps is configured for, forexample, linear ablation. In some embodiments, the inner conductorcomprises a dielectric layer enveloping a central transmission line. Insome embodiments, the dielectric element has near-zero conductivity. Insome embodiments, the device further comprises a stylet. In someembodiments, the device further comprises a tuning element for adjustingthe amount of energy delivered through the gap regions. In certainembodiments, when used in tissue ablation settings, the device isconfigured to deliver a sufficient amount of energy to ablate a tissueregion or cause thrombosis.

The energy delivery devices having a linear array of antennae componentsprovide numerous advantages over the currently available systems anddevices. For example, a major drawback with currently available medicaldevices that utilize microwave energy is that the emitted energy isprovided locally, thereby precluding delivery of energy over a deeperand denser scale. The devices of the present invention overcome thislimitation by providing an applicator device having a linear array ofantennae components configured to deliver energy (e.g., microwaveenergy) over a wider and deeper scale (e.g., as opposed to localdelivery). Such a device is particularly useful in the tissue ablationof dense and/or thick tissue regions (e.g., tumors, organ lumens) andparticularly deep tissue regions (e.g., large cardiac areas, brains,bones).

III. Processor

In some embodiments, the energy delivery systems of the presentinvention utilize processors that monitor and/or control one or more ofthe components of the system. In some embodiments, the processor isprovided within a computer module. The computer module may also comprisesoftware that is used by the processor to carry out one or more of itsfunctions. For example, in some embodiments, the systems of the presentinvention provide software for regulating the amount of microwave energyprovided to a tissue region through monitoring one or morecharacteristics of the tissue region including, but not limited to, thesize and shape of a target tissue, the temperature of the tissue region,and the like (e.g., through a feedback system) (see, e.g., U.S. patentapplication Ser. Nos. 11/728,460, 11/728,457, and 11/728,428; each ofwhich is herein incorporated by reference in their entireties). In someembodiments, the software is configured to provide information (e.g.,monitoring information) in real time. In some embodiments, the softwareis configured to interact with the energy delivery systems of thepresent invention such that it is able to raise or lower (e.g., tune)the amount of energy delivered to a tissue region. In some embodiments,the software is designed to prime coolants for distribution into, forexample, an energy delivery device such that the coolant is at a desiredtemperature prior to use of the energy delivery device. In someembodiments, the type of tissue being treated (e.g., liver) is inputtedinto the software for purposes of allowing the processor to regulate(e.g., tune) the delivery of microwave energy to the tissue region basedupon pre-calibrated methods for that particular type of tissue region.In other embodiments, the processor generates a chart or diagram basedupon a particular type of tissue region displaying characteristicsuseful to a user of the system. In some embodiments, the processorprovides energy delivering algorithms for purposes of, for example,slowly ramping power to avoid tissue cracking due to rapid out-gassingcreated by high temperatures. In some embodiments, the processor allowsa user to choose power, duration of treatment, different treatmentalgorithms for different tissue types, simultaneous application of powerto the antennas in multiple antenna mode, switched power deliverybetween antennas, coherent and incoherent phasing, etc. In someembodiments, the processor is configured for the creation of a databaseof information (e.g., required energy levels, duration of treatment fora tissue region based on particular patient characteristics) pertainingto ablation treatments for a particular tissue region based uponprevious treatments with similar or dissimilar patient characteristics.

In some embodiments, the processor is used to generate, for example, anablation chart based upon entry of tissue characteristics (e.g., tumortype, tumor size, tumor location, surrounding vascular information,blood flow information, etc.). In such embodiments, the processor coulddirect placement of the energy delivery device so as to achieve desiredablation based upon the ablation chart.

In some embodiments a software package is provided to interact with theprocessor that allows the user to input parameters of the tissue to betreated (e.g., type of tumor or tissue section to be ablated, size,where it is located, location of vessels or vulnerable structures, andblood flow information) and then draw the desired ablation zone on a CTor other image to provide the desired results. The probes may be placedinto the tissue, and the computer generates the expected ablation zonebased on the information provided. Such an application may incorporatefeedback. For example, CT, MRI, or ultrasound imaging or thermometry maybe used during the ablation. This data is fed back into the computer,and the parameters readjusted to produce the desired result.

As used herein, the terms “computer memory” and “computer memory device”refer to any storage media readable by a computer processor. Examples ofcomputer memory include, but are not limited to, random access memory(RAM), read-only memory (ROM), computer chips, optical discs (e.g.,compact discs (CDs), digital video discs (DVDs), etc.), magnetic disks(e.g., hard disk drives (HDDs), floppy disks, ZIP® disks, etc.),magnetic tape, and solid state storage devices (e.g., memory cards,“flash” media, etc.).

As used herein, the term “computer readable medium” refers to any deviceor system for storing and providing information (e.g., data andinstructions) to a computer processor. Examples of computer readablemedia include, but are not limited to, optical discs, magnetic disks,magnetic tape, solid-state media, and servers for streaming media overnetworks.

As used herein, the terms “processor” and “central processing unit” or“CPU” are used interchangeably and refer to a device that is able toread a program from a computer memory device (e.g., ROM or othercomputer memory) and perform a set of steps according to the program.

IV. Imaging Systems

In some embodiments, the energy delivery systems of the presentinvention utilize imaging systems comprising imaging devices. The energydelivery systems are not limited to particular types of imaging devices(e.g., endoscopic devices, stereotactic computer assisted neurosurgicalnavigation devices, thermal sensor positioning systems, motion ratesensors, steering wire systems, intraprocedural ultrasound, fluoroscopy,computerized tomography magnetic resonance imaging, nuclear medicineimaging devices triangulation imaging, thermoacoustic imaging, infraredand/or laser imaging, electromagnetic imaging) (see, e.g., U.S. Pat.Nos. 6,817,976, 6,577,903, and 5,697,949, 5,603,697, and InternationalPatent Application No. WO 06/005,579; each herein incorporated byreference in their entireties). In some embodiments, the systems utilizeendoscopic cameras, imaging components, and/or navigation systems thatpermit or assist in placement, positioning, and/or monitoring of any ofthe items used with the energy systems of the present invention.

In some embodiments, the energy delivery systems provide software isconfigured for use of imaging equipment (e.g., CT, MRI, ultrasound). Insome embodiments, the imaging equipment software allows a user to makepredictions based upon known thermodynamic and electrical properties oftissue, vasculature, and location of the antenna(s). In someembodiments, the imaging software allows the generation of athree-dimensional map of the location of a tissue region (e.g., tumor,arrhythmia), location of the antenna(s), and to generate a predicted mapof the ablation zone.

In some embodiments, the imaging systems of the present invention areused to monitor ablation procedures (e.g., microwave thermal ablationprocedures, radio-frequency thermal ablation procedures). The presentinvention is not limited to a particular type of monitoring. In someembodiments, the imaging systems are used to monitor the amount ofablation occurring within a particular tissue region(s) undergoing athermal ablation procedure. In some embodiments, the monitoring operatesalong with the ablation devices (e.g., energy delivery devices) suchthat the amount of energy delivered to a particular tissue region isdependent upon the imaging of the tissue region. The imaging systems arenot limited to a particular type of monitoring. The present invention isnot limited to what is being monitored with the imaging devices. In someembodiments, the monitoring is imaging blood perfusion for a particularregion so as to detect changes in the region, for example, before,during and after a thermal ablation procedure. In some embodiments, themonitoring includes, but is not limited to, MRI imaging, CT imaging,ultrasound imaging, nuclear medicine imaging, and fluoroscopy imaging.For example, in some embodiments, prior to a thermal ablation procedure,a contrast agent (e.g., iodine or other suitable CT contrast agent;gadolinium chelate or other suitable MRI contrast agent, microbubbles orother suitable ultrasound contrast agent, etc.) is supplied to a subject(e.g., a patient) and the contrast agent perfusing through a particulartissue region that is undergoing the ablation procedure is monitored forblood perfusion changes.

In some embodiments, the imaging systems are designed to automaticallymonitor a particular tissue region at any desired frequency (e.g., persecond intervals, per one-minute intervals, per ten-minute intervals,per hour-intervals, etc.). In some embodiments, the present inventionprovides software designed to automatically obtain images of a tissueregion (e.g., MRI imaging, CT imaging, ultrasound imaging, nuclearmedicine imaging, fluoroscopy imaging), automatically detect any changesin the tissue region (e.g., blood perfusion, temperature, amount ofnecrotic tissue, etc.), and based on the detection to automaticallyadjust the amount of energy delivered to the tissue region through theenergy delivery devices. Likewise, an algorithm may be applied topredict the shape and size of the tissue region to be ablated (e.g.,tumor shape) such that the system recommends the type, number, andlocation of ablation probes to effectively treat the region. In someembodiments, the system is configured to with a navigation or guidancesystem (e.g., employing triangulation or other positioning routines) toassist in or direct the placement of the probes and their use.

For example, such procedures may use the enhancement or lack ofenhancement of a contrast material bolus to track the progress of anablation or other treatment procedure. Subtraction methods may also beused (e.g., similar to those used for digital subtraction angiography).For example, a first image may be taken at a first time point.Subsequent images subtract out some or all of the information from thefirst image so that changes in tissue are more readily observed.Likewise, accelerated imaging techniques may be used that apply “undersampling” techniques (in contrast to Nyquist sampling). It iscontemplated that such techniques provide excellent signal-to-noiseusing multiple low resolutions images obtained over time. For example,an algorithm called HYPER (highly constrained projection reconstruction)is available for MRI that may be applied to embodiments of the systemsof the invention.

As thermal-based treatments coagulate blood vessels when tissuetemperatures exceed, for example, 50° C., the coagulation decreasesblood supply to the area that has been completely coagulated. Tissueregions that are coagulated do not enhance after the administration ofcontrast. In some embodiments, the present invention utilizes theimaging systems to automatically track the progress of an ablationprocedure by giving, for example, a small test injection of contrast todetermine the contrast arrival time at the tissue region in question andto establish baseline enhancement. In some embodiments, a series ofsmall contrast injections is next performed following commencement ofthe ablation procedure (e.g., in the case of CT, a series of up tofifteen 10 ml boluses of 300 mgI/ml water soluble contrast is injected),scans are performed at a desired appropriate post-injection time (e.g.,as determined from the test injection), and the contrast enhancement ofthe targeted area is determined using, for example, a region-of-interest(ROI) to track any one of a number of parameters including, but notlimited to, attenuation (Hounsfield Units [HU]) for CT, signal (MRI),echogenicity (ultrasound), etc. The imaged data is not limited to aparticular manner of presentation. In some embodiments, the imaging datais presented as color-coded or grey scale maps or overlays of the changein attenuation/signal/echogenicity, the difference between targeted andnon-targeted tissue, differences in arrival time of the contrast bolusduring treatment, changes in tissue perfusion, and any other tissueproperties that can be measured before and after the injection ofcontrast material. The methods of the present invention are not limitedto selected ROI's, but can be generalized to all pixels within anyimage. The pixels can be color-coded, or an overlay used to demonstratewhere tissue changes have occurred and are occurring. The pixels canchange colors (or other properties) as the tissue property changes, thusgiving a near real-time display of the progress of the treatment. Thismethod can also be generalized to 3d/4d methods of image display.

In some embodiments, the area to be treated is presented on a computeroverlay, and a second overlay in a different color or shading yields anear real-time display of the progress of the treatment. In someembodiments, the presentation and imaging is automated so that there isa feedback loop to a treatment technology (RF, MW, HIFU, laser, cryo,etc) to modulate the power (or any other control parameter) based on theimaging findings. For example, if the perfusion to a targeted area isdecreased to a target level, the power could be decreased or stopped.For example, such embodiments are applicable to a multiple applicatorsystem as the power/time/frequency/duty cycle, etc. is modulated foreach individual applicator or element in a phased array system to createa precisely sculpted zone of tissue treatment. Conversely, in someembodiments, the methods are used to select an area that is not to betreated (e.g., vulnerable structures that need to be avoided such asbile ducts, bowel, etc.). In such embodiments, the methods monitortissue changes in the area to be avoided, and warn the user (e.g.,treating physician) using alarms (e.g., visible and/or audible alarms)that the structure to be preserved is in danger of damage. In someembodiments, the feedback loop is used to modify power or any otherparameter to avoid continued damage to a tissue region selected not tobe treated. In some embodiments, protection of a tissue region fromablation is accomplished by setting a threshold value such as a targetROI in a vulnerable area, or using a computer overlay to define a “notreatment” zone as desired by the user.

V. Tuning Systems

In some embodiments, the energy delivery systems of the presentinvention utilize tuning elements for adjusting the amount of energydelivered to the tissue region. In some embodiments, the tuning elementis manually adjusted by a user of the system. In some embodiments, atuning system is incorporated into an energy delivery device so as topermit a user to adjust the energy delivery of the device as desired(see, e.g., U.S. Pat. Nos. 5,957,969, 5,405,346; each hereinincorporated by reference in their entireties). In some embodiments, thedevice is pretuned to the desired tissue and is fixed throughout theprocedure. In some embodiments, the tuning system is designed to matchimpedance between a generator and an energy delivery device (see, e.g.,U.S. Pat. No. 5,364,392; herein incorporated by reference in itsentirety). In some embodiments, the tuning element is automaticallyadjusted and controlled by a processor of the present invention (see,e.g., U.S. Pat. No. 5,693,082; herein incorporated by reference in itsentirety). In some embodiments, a processor adjusts the energy deliveryover time to provide constant energy throughout a procedure, taking intoaccount any number of desired factors including, but not limited to,heat, nature and/or location of target tissue, size of lesion desired,length of treatment time, proximity to sensitive organ areas or bloodvessels, and the like. In some embodiments, the system comprises asensor that provides feedback to the user or to a processor thatmonitors the function of the device continuously or at time points. Thesensor may record and/or report back any number of properties,including, but not limited to, heat at one or more positions of acomponents of the system, heat at the tissue, property of the tissue,and the like. The sensor may be in the form of an imaging device such asCT, ultrasound, magnetic resonance imaging, or any other imaging device.In some embodiments, particularly for research application, the systemrecords and stores the information for use in future optimization of thesystem generally and/or for optimization of energy delivery underparticular conditions (e.g., patient type, tissue type, size and shapeof target region, location of target region, etc.).

VI. Temperature Adjustment Systems

In some embodiments, the energy delivery systems of the presentinvention utilize coolant systems so as to reduce undesired heatingwithin and along an energy delivery device (e.g., tissue ablationcatheter). The systems of the present invention are not limited to aparticular cooling system mechanism. In some embodiments, the systemsare designed to circulate a coolant (e.g., air, liquid, etc.) throughoutan energy delivery device such that the coaxial transmission line(s) andantenna(e) temperatures are reduced. In some embodiments, the systemsutilize energy delivery devices having therein channels designed toaccommodate coolant circulation. In some embodiments, the systemsprovide a coolant sheath wrapped around the antenna or portions of theantenna for purposes of cooling the antenna externally (see, e.g., U.S.patent application Ser. No. 11/053,987; herein incorporated by referencein its entirety). In some embodiments, the systems utilize energydelivery devices having a conductive covering around the antenna forpurposes of limiting dissipation of heat onto surrounding tissue (see,e.g., U.S. Pat. No. 5,358,515; herein incorporated by reference in itsentirety). In some embodiments, upon circulation of the coolant, it isexported into, for example, a waste receptacle. In some embodiments,upon circulation of the coolant it is recirculated.

In some embodiments, the systems utilize expandable balloons inconjunction with energy delivery devices for purposes of urging tissueaway from the surface of the antenna(e) (see, e.g., U.S. patentapplication Ser. No. 11/053,987; herein incorporated by reference in itsentirety).

In some embodiments, the systems utilize devices configured to attachonto an energy delivery device for purposes of reducing undesiredheating within and along the energy delivery device (see, e.g., U.S.patent application Ser. No. 11/237,430; herein incorporated by referencein its entirety).

VII. Identification Systems

In some embodiments, the energy delivery systems of the presentinvention utilize identification elements (e.g., RFID elements,barcodes, etc.) associated with one or more components of the system. Insome embodiments, the identification element conveys information about aparticular component of the system. The present invention is not limitedby the information conveyed. In some embodiments, the informationconveyed includes, but is not limited to, the type of component (e.g.,manufacturer, size, energy rating, tissue configuration, etc.), whetherthe component has been used before (e.g., so as to ensure thatnon-sterile components are not used), the location of the component,patient-specific information and the like. In some embodiments, theinformation is read by a processor of the present invention. In somesuch embodiments, the processor configures other components of thesystem for use with, or for optimal use with, the component containingthe identification element.

In some embodiments, the energy delivery devices have thereon markings(e.g., scratches, color schemes, etchings, painted contrast agentmarkings, and/or ridges) so as to improve identification of a particularenergy delivery device (e.g., improve identification of a particulardevice located in the vicinity of other devices with similarappearances). The markings find particular use where multiple devicesare inserted into a patient. In such cases, particularly where thedevices may cross each other at various angles, it is difficult for thetreating physician to associate which proximal end of the device,located outside of the patient body, corresponds to which distal end ofthe device, located inside the patient body. In some embodiments, amarking (e.g., a number) a present on the proximal end of the device sothat it is viewable by the physician's eyes and a second marking (e.g.,that corresponds to the number) is present on the distal end of thedevice so that it is viewable by an imaging device when present in thebody. In some embodiments, where a set of antennas is employed, theindividual members of the set are numbered (e.g., 1, 2, 3, 4, etc.) onboth the proximal and distal ends. In some embodiments, handles arenumbered, a matching numbered detachable (e.g., disposable) antennas areconnected to the handles prior to use. In some embodiments, a processorof the system ensures that the handles and antennas are properly matched(e.g., by RFID tag or other means). In some embodiments, where theantenna are disposable, the system provides a warning if a disposablecomponent is attempted to be re-used, when it should have beendiscarded. In some embodiments, the markings improve identification inany type of detection system including, but not limited to, MRI, CT, andultrasound detection.

The energy delivery systems of the present invention are not limited toparticular types of tracking devices. In some embodiments, GPS and GPSrelated devices are used. In some embodiments, RFID and RFID relateddevices are used. In some embodiments, barcodes are used.

In such embodiments, authorization (e.g., entry of a code, scanning of abarcode) prior to use of a device with an identification element isrequired prior to the use of such a device. In some embodiments, theinformation element identifies that a components has been used beforeand sends information to the processor to lock (e.g. block) use ofsystem until a new, sterile component is provided.

VIII. Temperature Monitoring Systems

In some embodiments, the energy delivering systems of the presentinvention utilize temperature monitoring systems. In some embodiments,temperature monitoring systems are used to monitor the temperature of anenergy delivery device (e.g., with a temperature sensor). In someembodiments, temperature monitoring systems are used to monitor thetemperature of a tissue region (e.g., tissue being treated, surroundingtissue). In some embodiments, the temperature monitoring systems aredesigned to communicate with a processor for purposes of providingtemperature information to a user or to the processor to allow theprocessor to adjust the system appropriately.

IX. Other Components

The system of the present invention may further employ one or moreadditional components that either directly or indirectly take advantageof or assist the features of the present invention. For example, in someembodiments, one or more monitoring devices are used to monitor and/orreport the function of any one or more components of the system.Additionally, any medical device or system that might be used, directlyor indirectly, in conjunction with the devices of the present inventionmay be included with the system. Such components include, but are notlimited to, sterilization systems, devices, and components; othersurgical, diagnostic, or monitoring devices or systems; computerequipment; handbooks, instructions, labels, and guidelines; roboticequipment; and the like.

In some embodiments, the systems employ pumps, reservoirs, tubing,wiring, or other components that provide materials on connectivity ofthe various components of the systems of the present invention. Forexample, any type of pump may be used to supply gas or liquid coolantsto the antennas of the present invention. Gas or liquid handling tankscontaining coolant may be employed in the system.

In certain embodiments, the energy delivery systems (e.g., the energydelivery device, the processor, the power supply, the imaging system,the temperature adjustment system, the temperature monitoring system,and/or the identification systems) and all related energy deliverysystem utilization sources (e.g., cables, wires, cords, tubes, pipesproviding energy, gas, coolant, liquid, pressure, and communicationitems) are provided in a manner that reduces undesired presentationproblems (e.g., tangling, cluttering, and sterility compromiseassociated with unorganized energy delivery system utilization sources).The present invention is not limited to a particular manner of providingthe energy delivery systems and energy delivery system utilizationsources such that undesired presentation problems are reduced. In someembodiments, as shown in FIG. 13, the energy delivery systems and energydelivery system utilization sources are organized with an import/exportbox 1300, a transport sheath 1310, and a procedure device hub 1320.

The present invention is not limited to a particular type or kind ofimport/export box. In some embodiments, the import/export box containsthe power supply and coolant supply. In some embodiments, theimport/export box is located outside of a sterile field in which thepatient is being treated. In some embodiments, the import/export box islocated outside of the room in which the patient is being treated. Insome embodiments, one or more cables connect the import/export box to aprocedure device hub. In some embodiments, a single cable is used (e.g.,a transport sheath). For example, in some such embodiments, a transportsheath contains components for delivery of both energy and coolant toand/or from the import/export box. In some embodiments, the transportsheath connects to the procedure device hub without causing a physicalobstacle for medical practitioners (e.g., travels under the floor,overhead, etc.

The present invention is not limited to a particular type or kind ofprocedure device hub. In some embodiments, the procedure device hub isconfigured to receive power, coolant, or other elements from theimport/export box or other sources. In some embodiments, the proceduredevice hub provides a control center, located physically near thepatient, for any one or more of: delivering energy to a medical device,circulating coolant to a medical device, collecting and processing data(e.g., imaging data, energy delivery data, safety monitoring data,temperature data, and the like), and providing any other function thatfacilitates a medical procedure. In some embodiments, the proceduredevice hub is configured to engage the transport sheath so as to receivethe associated energy delivery system utilization sources. In someembodiments, the procedure device hub is configured to receive anddistribute the various energy delivery system utilization sources to theapplicable devices (e.g., energy delivery devices, imaging systems,temperature adjustment systems, temperature monitoring systems, and/oridentification systems). For example, in some embodiments, the proceduredevice hub is configured to receive microwave energy and coolant fromenergy delivery system utilization sources and distribute the microwaveenergy and coolant to an energy delivery device. In some embodiments,the procedure device hub is configured to turn on or off, calibrate, andadjust (e.g., automatically or manually) the amount of a particularenergy delivery system utilization source as desired. In someembodiments, the procedure device hub has therein a power splitter foradjusting (e.g., manually or automatically turning on, turning off,calibrating) the amount of a particular energy delivery systemutilization source as desired. In some embodiments, the procedure devicehub has therein software designed to provide energy delivery systemutilization sources in a desired manner. In some embodiments, theprocedure device hub has a display region indicating associatedcharacteristics for each energy delivery system utilization source. Insome embodiments, the processor associated with the energy deliverysystem is located in the procedure device hub. In some embodiments, thepower supply associated with the energy delivery systems is locatedwithin the procedure device hub. In some embodiments, the proceduredevice hub has a sensor configured to automatically inhibit one or moreenergy delivery system utilization sources upon the occurrence of anundesired-event (e.g., undesired heating, undesired leak, undesiredchange in pressure, etc.).

In some embodiments, the procedure device hub is designed for locationwithin a sterile setting. In some embodiments, the procedure device hubis positioned on a patient's bed, a table that the patient is on (e.g.,a table used for CT imaging, MRI imaging, etc.), or other structure nearthe patient. In some embodiments, the procedure device hub is positionedon a separate table. In some embodiments, the procedure device hub isattached to a ceiling. In some embodiments, the procedure device hub isattached to a ceiling such that a user (e.g., a physician) may move itinto a desired position (thereby avoiding having to position the energydelivery system utilization sources (e.g., cables, wires, cords, tubes,pipes providing energy, gas, coolant, liquid, pressure, andcommunication items) on or near a patient while in use). In someembodiments, the procedure device hub is configured to communicate(wirelessly or via wire) with a processor (e.g., a computer, with theInternet, with a cellular phone, with a PDA). In some embodiments, theprocedure device hub has thereon one or more lights. In someembodiments, the procedure device hub is configured to compresstransported coolants (e.g., CO₂) at any desired pressure so as to, forexample, retain the coolant at a desired pressure (e.g., the criticalpoint for a gas) so as to improve cooling or temperature maintenance.For example, in some embodiments, a gas is provided at or near itscritical point for the purpose of maintaining a temperature of a device,line, cable, or other component at or near a constant, definedtemperature. In some such embodiments, a component is not cooled per se,in that its temperature does not drop from a starting temperature (e.g.,room temperature), but instead is maintained at a constant temperaturethat is cooler than where the component would be, but for theintervention. For example, CO₂ may be used at or near its critical point(e.g., 31.1 Celsius at 78.21 kPa) to maintain temperature so thatcomponents of the system are sufficiently cool enough not to burntissue, but likewise are not cooled or maintained significantly belowroom temperature or body temperature such skin in contact with thecomponent freezes or is otherwise damaged by cold. Using suchconfigurations permits the use of less insulation, as there are not“cold” components that must be shielded from people or from the ambientenvironment. In some embodiments, the procedure device hub has aretracting element designed to recoil used and/or unused cables, wires,cords, tubes, and pipes providing energy, gas, coolant, liquid,pressure, and/or communication items. In some embodiments, the proceduredevice hub is configured to prime coolants for distribution into, forexample, an energy delivery device such that the coolant is at a desiredtemperature prior to use of the energy delivery device. In someembodiments, the procedure device hub has therein software configured toprime coolants for distribution into, for example, an energy deliverydevice such that the system is at a desired temperature prior to use ofthe energy delivery device. In some embodiments, the use of a proceduredevice hub permits the use of shorter cables, wires, cords, tubes,and/or pipes (e.g., less than 4 feet, 3 feet, 2 feet). In someembodiments, the procedure device hub and/or one more componentsconnected to it, or portions thereof are covered by a sterile sheath.

In one illustrative embodiment, a import/export box contains one or moremicrowave power sources and a coolant supply (e.g., pressurized carbondioxide gas). This import/export box is connected to a single transportsheath that delivers both the microwave energy and coolant to aprocedure device hub. The coolant line or the energy line within thetransport sheath may be wound around one another to permit maximumcooling of the transport sheath itself. The transport sheath is run intothe sterile field where a procedure it to take place along the floor ina location that does not interfere with the movement of the medical teamattending to the patient. The transport sheath connects to a tablelocated near an imaging table upon which a patient lays. The table isportable (e.g., on wheels) and connectable to the imaging table so thatthey move together. The table contains arm, which may be flexible ortelescoping, so as to permit positioning of the arm above and over thepatient. The transport sheath, or cables connected to the transportsheath, run along the arm to the overhead position. At the end of thearm is the procedure device hub. In some embodiments, two or more armsare provided with two or more procedure device hubs or two or moresub-components of a single procedure device hub. The procedure devicehub is small (e.g., less than 1 foot cube, less than 10 cm cube, etc.)to allow easy movement and positioning above the patient. The proceduredevice hub contains a processor for controlling all computing aspects ofthe system. The device hub contains one or more connections ports forconnecting cables that lead to energy delivery devices. Cables areconnected to the ports. The cables are retractable and less than threefeet in length. Use of short cables reduces expense and prevents powerloss. When not in use, the cables hang in the air above the patient, outof contact with the patient's body. The ports are configured with adummy load when not in use (e.g., when a energy delivery device is notconnected to a particular port). The procedure device hub is withinreach of the treating physician so that computer controls can beadjusted and displayed information can be viewed, in real-time, during aprocedure.

X. Uses for Energy Delivery Systems

The systems of the present invention are not limited to particular uses.Indeed, the energy delivery systems of the present invention aredesigned for use in any setting wherein the emission of energy isapplicable. Such uses include any and all medical, veterinary, andresearch applications. In addition, the systems and devices of thepresent invention may be used in agricultural settings, manufacturingsettings, mechanical settings, or any other application where energy isto be delivered.

In some embodiments, the systems are configured for open surgery,percutaneous, intravascular, intracardiac, endoscopic, intraluminal,laparoscopic, or surgical delivery of energy. In some embodiments, thesystems are configured for delivery of energy to a target tissue orregion. In some embodiments, a positioning plate is provided so as toimprove percutaneous, intravascular, intracardiac, laparoscopic, and/orsurgical delivery of energy with the energy delivery systems of thepresent invention. The present invention is not limited to a particulartype and/or kind of positioning plate. In some embodiments, thepositioning plate is designed to secure one or more energy deliverydevices at a desired body region for percutaneous, intravascular,intracardiac, laparoscopic, and/or surgical delivery of energy. In someembodiments, the composition of the positioning plate is such that it isable to prevent exposure of the body region to undesired heat from theenergy delivery system. In some embodiments, the plate provides guidesfor assisted positioning of energy delivery devices. The presentinvention is not limited by the nature of the target tissue or region.Uses include, but are not limited to, treatment of heart arrhythmia,tumor ablation (benign and malignant), control of bleeding duringsurgery, after trauma, for any other control of bleeding, removal ofsoft tissue, tissue resection and harvest, treatment of varicose veins,intraluminal tissue ablation (e.g., to treat esophageal pathologies suchas Barrett's Esophagus and esophageal adenocarcinoma), treatment of bonytumors, normal bone, and benign bony conditions, intraocular uses, usesin cosmetic surgery, treatment of pathologies of the central nervoussystem including brain tumors and electrical disturbances, sterilizationprocedures (e.g., ablation of the fallopian tubes) and cauterization ofblood vessels or tissue for any purposes. In some embodiments, thesurgical application comprises ablation therapy (e.g., to achievecoagulative necrosis). In some embodiments, the surgical applicationcomprises tumor ablation to target, for example, metastatic tumors. Insome embodiments, the device is configured for movement and positioning,with minimal damage to the tissue or organism, at any desired location,including but not limited to, the brain, neck, chest, abdomen, andpelvis. In some embodiments, the systems are configured for guideddelivery, for example, by computerized tomography, ultrasound, magneticresonance imaging, fluoroscopy, and the like.

In certain embodiments, the present invention provides methods oftreating a tissue region, comprising providing a tissue region and asystem described herein (e.g., an energy delivery device, and at leastone of the following components: a processor, a power supply, atemperature monitor, an imager, a tuning system, and/or a temperaturereduction system); positioning a portion of the energy delivery devicein the vicinity of the tissue region, and delivering an amount of energywith the device to the tissue region. In some embodiments, the tissueregion is a tumor. In some embodiments, the delivering of the energyresults in, for example, the ablation of the tissue region and/orthrombosis of a blood vessel, and/or electroporation of a tissue region.In some embodiments, the tissue region is a tumor. In some embodiments,the tissue region comprises one or more of the heart, liver, genitalia,stomach, lung, large intestine, small intestine, brain, neck, bone,kidney, muscle, tendon, blood vessel, prostate, bladder, and spinalcord.

EXPERIMENTAL Example I

This example demonstrates the avoidance of undesired tissue heatingthrough use of an energy delivery device of the present inventioncirculating coolant through coolant channels. The ablation needle shaftfor all experiments was 20.5 cm. There was minimal cooling of the handleassembly indicating that handle-cooling effects were well-isolated.Temperature probes 1, 2 and 3 were located at 4, 8 and 12 cm proximal tothe tip of the stainless needle (see FIG. 9). Temperature measurementswere taken for 35% power measurement following insertion into a pigliver and 45% power measurement following insertion into a pig liver.For the 35% power measurement, Probe 4 was on the handle itself. For the45% power measurements, Probe 4 was located at the needle-skininterface, approximately 16 cm back from the stainless needle tip.

As shown in FIG. 10, treatment at 35% power for 10 minutes withanonymously high (6.5%) reflected power demonstrated maintenance of thedevice at a non-tissue damaging temperature at Probes 1, 2, 3 and thehandle.

As shown in FIG. 11, treatment at 45% power for 10 minutes withanonymously high (6.5%) reflected power demonstrated maintenance of thedevice at a non-tissue damaging temperature at Probes 1, 2, 3 and 4.Observation of the skin and fat layers after 10 minutes ablation at 45%power for 10 minutes with anonymously high (6.5%) reflected powerdemonstrating no visible burns or thermal damage.

Example II

This example demonstrates generator calibration. Generator calibrationwas done by Cober-Muegge at the factory and was set to be most accuratefor powers greater than 150 W. The magnetron behaved much like a diode:increasing cathode voltage did not increase vacuum current (proportionalto output power) until a critical threshold was reached, at which pointvacuum current increased rapidly with voltage. Control of the magnetronsource relied on accurate control of the cathode voltage near thatcritical point. As such, the generator was not specified for powers from0-10% and correlation between the output power and theoretical powerpercentage input was poor below 15%.

To test the generator calibration, the power control dial was changedfrom 0.25% in 1% increments (corresponding to theoretical output powersof 0-75 W in 3 W increments) and the generator's output power displaywas recorded and power output measured. The measured power output wasadjusted for the measured losses of the coaxial cable, coupler and loadat room temperature. The output display was also adjusted for offseterror (i.e., the generator read 2.0% when the dial was set to 0.0%).

The error between the dial and generator output power display was largefor low-power dial settings. These two values quickly converged to apercent error of less than 5% for dial settings above 15%. Similarly,the measured output power was significantly different from thetheoretical output power for dial settings below 15% but more accuratefor dial settings above 15%.

Example III

This example describes the setup and testing of an antenna duringmanufacturing. This provides a method for setup and tested in amanufacturing environment. The method employs a liquid,tissue-equivalent phantom rather than tissue.

From the numerical and experimental measurements already made on theantenna, it was known that changes in L2 of ˜1 mm will increase thereflected power from <−30 dB to ˜−20-25 dB. This increase was likelymade less significant by the changes in tissue properties that occurredduring ablation and so we would consider at relative tolerance of 0.5 mmon the length L2 is reasonable. Likewise, a tolerance of 0.5 mm on thelength L1 is used, even though the total reflection coefficient dependsless on L1 than L2.

Testing of the antenna tuning for quality control purposes can beachieved using a liquid solution designed to mimic the dielectricproperties of liver, lung or kidney (see, e.g., Guy AW (1971) IEEETrans. Microw. Theory Tech. 19:189-217; herein incorporated by referencein its entirety). The antenna is immersed in the phantom and thereflection coefficient recorded using a 1-port measurement device orfull vector network analyzer (VNA). Verification of a reflectioncoefficient below −30 dB is selected to ensure proper tuning.

All publications and patents mentioned in the above specification areherein incorporated by reference. Various modifications and variationsof the described method and system of the invention will be apparent tothose skilled in the art without departing from the scope and spirit ofthe invention. Although the invention has been described in connectionwith specific embodiments, it should be understood that the invention asclaimed should not be unduly limited to such specific embodiments.Indeed, various modifications of the described modes for carrying outthe invention that are obvious to those skilled in the relevant fieldsare intended to be within the scope of the following claims.

1. A device comprising an antenna configured for delivery of energy to atissue, said antenna having a cooling channel provided in an inner orouter conductor of a coaxial cable.
 2. A device comprising an antennaconfigured for delivery of energy to a tissue, said antenna comprisingan expandable material that changes volume in response to heat, whereina change in volume alters energy delivery characteristics of theantenna.
 3. The device of claim 2, wherein said antenna comprises acenter-fed dipole and said expandable material is contained in saidcenter-fed dipole.
 4. A device comprising an antenna configured fordelivery of energy to a tissue, said antenna comprising first and secondchemicals that, when in contact with one another, create an endothermicreaction configured to cools said antenna.
 5. The device of claim 4,wherein said first and second chemicals are separated from one anotherby a barrier.
 6. The device of claim 5, wherein said barrier isconfigured to be removed in response to heat.
 7. The device of claim 4,wherein said first and second chemicals are preloaded in said antennaprior to use.
 8. The device of claim 4, wherein said first or secondchemicals are supplied to said antenna during use.
 9. A devicecomprising an antenna configured for delivery of energy to a tissue,said antenna comprising one or more cooling tubes inserted within acoaxial cable, said tubes configured to deliver coolant to said antenna.10. The device of claim 9, wherein said one or more coolant tubes arebetween an outer conductor and dielectric material of said coaxialcable.
 11. The device of claim 9, wherein said one or more coolant tubesare between an inner conductor and dielectric material of said coaxialcable.
 12. The device of claim 9, wherein said one or more coolant tubeare within an inner or outer conductor.
 13. A device comprising anantenna configured for delivery of energy to a tissue, said antennacomprising two or more segments separated by a gap in an outer conductorof a coaxial cable, said gap filled with a resin.
 14. The device ofclaim 13, wherein said resin comprises a curable epoxy resin.
 15. Adevice comprising an antenna configured for delivery of energy to atissue, wherein the antenna comprises a coaxial cable and wherein theantenna has a non-circular cross-sectional shape.
 16. The device ofclaim 15, wherein said coaxial cable has a non-circular cross-sectionalshape.
 17. The device of claim 16, wherein a dielectric component ofsaid coaxial cable has a non-circular shape.
 18. A system comprising: a)a power source component that provides an energy source and a coolantsource; b) a transport component for delivering energy and coolant fromthe power source component to a control hub; and c) a portable controlhub that receives energy and coolant from the transport component, saidcontrol hub positioned on a mobile arm, positionable above a patientworkspace; said control hub comprising: i) a processor for regulatingenergy and coolant delivery to a plurality of energy delivery devices;and ii) a plurality of connection ports for attachment of cablesconfigured to delivery energy to energy delivery devices.
 19. The systemof claim 18, wherein said power source is located outside of a sterilefield and said control hub is located within a sterile field.
 20. Thesystem of claim 18, wherein said power source supplies microwave energy.21. The system of claim 18, wherein said power source suppliesradio-frequency energy.
 22. A system for monitoring and controllingablation therapy, comprising: a) one or more ablation devices configuredfor tissue ablation in a subject; and b) a processor that runs animaging and control program, said program comprising: a component formonitoring the position of said one or more ablation devices; acomponent for monitoring tissue status in the vicinity of said ablationdevices; and a component for reporting tissue status information to amedical practitioner.
 23. The system of claim 22, wherein said one ormore ablation devices comprise microwave energy delivery devices. 24.The system of claim 22, wherein said one or more ablation devicescomprise radiofrequency energy delivery devices.
 25. The system of claim22, wherein said processor provides a component for displaying arepresentation of a tissue region.
 26. The system of claim 25, whereinsaid processor further provides a component for permitting a user of thesystem to select a region on said displayed representation, of an areato be ablated.
 27. The system of claim 26, wherein said processorfurther provides a component for automated treatment of said selectedregion.
 28. The system of claim 27, wherein said automated treatmentcomprises energy delivery control.
 29. The system of claim 27, whereinsaid automated treatment comprises monitoring tissue status at one ormore time points.
 30. The system of claim 29, wherein said monitoringtissue comprises monitoring location of a contrast agent in said tissue.31. The system of claim 22, wherein said program components are providedby software run by said processor.